Momo was born into a famous hero family, gaining a powerful Quirk as a result. Due to the vast wealth of her family, she had access to various objects to study and practice within her home as a child, with the Russian matryoshka dolls being her favoured tool for Quirk training.
Being raised by a strict mother who told her to only need fundamental and urgent things, Momo grew somewhat lonely and didn't go to festivals like other children. During her teenage years, Momo was accepted into U.A. through official recommendations. She currently tops her class in grades, always coming out 1st.
Having gained entry to U.A. High through recommendations, Momo Yaoyorozu attends the first day of school with Class 1-A. Their homeroom teacher Shota Aizawa immediately brings the class to the training field for a Quirk Apprehension Test and claims that whoever comes in last will be expelled.
Momo manages to score first place in the entire class while Izuku Midoriya comes in last. Shota then reveals that he was lying about expelling the last place student to make sure the students did their best. Seeing everyone's shocked reaction to the news, Momo tells them she's surprised they didn't realize that earlier and says she should have mentioned it.
Momo answers one of Present Mic's questions in English class the next morning. That afternoon, Class 1-A participates in combat training for their Hero Basic Training class taught by All Might. They meet him at training ground beta after changing into their hero costumes. He splits them up into teams of two and has them simulate a hero versus villain situation. Momo ends up paired with Minoru on Team C.
Following the first battle trial, All Might states Tenya Iida was the best in the battle despite his team's failure. He asks the students why this is the case and Momo responds. She replies that Tenya embraced the spirit of the trial while Ochaco let her guard down, Izuku rendered himself helpless and Katsuki's judgment was clouded by a grudge. She goes on to say that she and her classmates must devote themselves wholeheartedly if they wish to become Pro-Heroes.
The next day in homeroom class, Shota tells the class they need to choose their Class President. The class follows Tenya's suggestion of voting for the president and Momo gets the second most votes behind Izuku. To her dismay, she is made Vice-President while Izuku becomes the Class President. However, when it comes time to decide who the Class Officers will be, Izuku decides to give his role to Tenya. This leaves Momo discouraged because she still believes that she should be the representative. Later on, Shota announces to the Class that they will partake in rescue training at an outside facility.
During the bus trip to the aforementioned facility, Momo tells Ochaco that the argument between Katsuki and others is too vulgar. Class 1-A arrives at the Unforeseen Simulation Joint, where they meet the Space Hero: Thirteen. Thirteen explains she developed the U.S.J with the focus on training future heroes on using their Quirks to help others. Suddenly during Thirteen's speech, real villains invade the facility through a warp gate. Shota fends off the villains on his own and leaves Thirteen to evacuate with the class. They prepare to escape, but they are cut off by the villain Kurogiri. Katsuki and Eijiro attack him, but end up dealing no damage. Kurogiri responds by warping the class to the various areas in the facility. Momo is warped to the Mountain Zone along with Kyoka and Denki. She uses her Quirk to create a metal staff for herself and a sword for Kyoka to defend themselves.
While they're surrounded by villains, Denki mentions that he cannot shoot out his electricity or else he'll shock the girls too. Annoyed, Kyoka kicks him into a villain so that he can electrocute them. Another villain tries to get the jump on them, but Momo uses her Quirk to trap him in a net and he falls into Denki's electrical field as well. Momo creates a sheet of insulation to protect herself and Kyoka. She tells Denki he can attack without restraint and so he blasts the villains with an electric attack, and ends up destroying most of Momo's shirt. Kyoka points this out, but Momo replies that she can simply make new clothes. 
Denki's Quirk renders him helpless after he overuses it, leaving him open to an electric villain hiding underground. He warns Momo and Kyoka to surrender and threatens to kill Denki. Momo notices Kyoka trying to distract him while using her Quirk, but he quickly becomes wise to her act. Before it's too late, the trio is saved when the Pro Heroes arrive at the facility. Snipe uses his Quirk to shoot the villain multiple times to free Denki. Then Ectoplasm arrives to escort the students out and take the villains into custody. Afterward, Detective Tsukauchi takes Class 1-A back to U.A. High.
Two days after the attack on the U.S.J., Momo and her classmates return to school discuss the attack. After Shota returns to class, the students get lectured about the importance of the upcoming U.A. Sports Festival. Momo mentions that she's excited about the opportunity to get scouted. For the next two weeks before the festival, Momo trains by reading up on the molecular structures of the items she can create. The day of the U.A. Sports Festival arrives and Momo changes into her P.E. clothes and prepares with her classmates in their designated waiting room. Like the rest of her peers, Momo takes notice when Shoto challenges Izuku.
Chief referee of the Sports Festival: Midnight announces the preliminaries will be an Obstacle Race four kilometers around the stadium, which immediately begins after the rules are explained. The students begin the race jam-packed inside a narrow corridor. Shoto freezes the tight space and gets out to an early lead, but Momo and others use their Quirks to avoid it. They all reach the first obstacle, which is a blockade of giant villain bots. Momo uses her Quirk to create a cannon and effectively shoots all of them down to clear the path. After reaching the minefield, Momo is attacked by Minoru, who uses his Quirk to stick to her back and piggy-back on her all the way to the finish line. She finishes in seventeenth place while carrying Minoru against her will. After completing the race, she tells him that he is the worst. This qualifies them both for the second event: The Cavalry Battle.
Shoto chooses Momo for his team along with Denki and Tenya. He tells Momo that her role on the right wing provides insolation and defense for the team. She creates skates for herself and Denki so that the team can move very quickly and take advantage of Tenya's speed in the front of the formation. Towards the middle of the event, Team Todoroki confronts Team Midoriya for their ten million point headband. They attack Team Midoriya at the same time as many other teams. Shoto orders Momo to ready her Quirk to protect them from Denki's lightning. She also creates a stone staff for Shoto to use. Denki electrocutes the other teams and Shoto uses the staff and his ice powers to freeze them all in place. Fumikage was able to defend against Denki's attack, giving Team Midoriya the chance to flee. Team Todoroki proves to be too fast for them to get away. Fumikage attacks with his Dark Shadow to stop their pursuit, but Momo defends Shoto by creating a block of stone to impede Dark Shadow's attack. Team Todoroki corners their opponent, but Team Midoriya is able to keep away from them by exploiting Shoto's weakness and keeping to his left side.
With only a minute left in the competition, Tenya decides to use his Recipro Burst technique to steal the ten million point headband. In an instant, Shoto grabs the points by using Tenya's burst of super speed. Although, it renders the team immobile afterward since Tenya's engines become stalled. Team Midoriya attacks in a last-ditch effort to get their points back but ends up grabbing the incorrect headband. Momo mentions that they mixed up the headbands knowing Team Midoriya would underestimate them. Once the Cavalry Battle concludes, Team Todoroki finishes in first place and all their members move on to the finals: a one on one fighting tournament. Tenya apologizes for nearly costing them the competition, and Momo encourages him by saying he's the reason they won at all.
Prior to the finals, all the participants are allowed an intermission for recreational games and rest. Momo goes to get food with Kyoka and they're both told by Denki and Minoru that they must dress up as cheerleaders for the cheer battle. Momo believes them and makes cheerleading outfits for the girls in Class 1-A, but this turns out to just be a prank from the boys. Momo yells at them and then falls into dismay for falling into their scheme. Midnight calls all the students to draw lots for the fighting matchups and Mashirao suddenly decides to withdraw from the tournament, surprising Momo and others. He explains that he was simply Hitoshi's puppet and doesn't wish to advance, and he also questions why the girls are dressed as cheerleaders. Momo and the girls are embarrassed by this.
Momo ends up matched up against Fumikage for the sixth battle. Fumikage promises to give it his best, which Momo appreciates. During the recreational games, Momo reluctantly cheers with the other girls. The first round's sixth fight eventually arrives and Momo takes the stage to face Fumikage. She is visibly nervous for their bout since Fumikage's Quirk allows him to effectively attack and defend. She ponders over a strategy to defend herself by creating a shield, but she's interrupted when the battle suddenly starts. Fumikage calls Dark Shadow to attack immediately and Momo blocks it with a shield just like she planned. She tries to follow up by making a weapon, but Dark Shadow keeps pressuring her by attacking her shield repeatedly. She's unable to focus on her Quirk until Fumikage mysteriously stops attacking. Momo creates a staff and prepares to counterattack until Midnight points out that she's pushed out of bounds. Fumikage is named the victor in the quickly ended bout, greatly disappointing Momo.
Momo watches the rest of the matches from the stands alongside her peers. She and Mina wonder why Fumikage is put on the defensive during his battle with Katsuki since he defeated them both so easily. After Katsuki wins the Sports Festival, Momo joins her peers for the closing ceremony.
Class resumes at U.A. two days after the Sports Festival. Momo joins her class in learning about Hero Informatics during homeroom. Shota reveals the Pro-Hero draft results, with Momo receiving one-hundred and eight offers from pros. Midnight joins the class to help the students choose their hero names. Momo chooses the moniker Everything Hero: "Creati".The students are given personalized lists of hero agencies they are to choose from along with their nominations. When the internship week arrives, Momo and her class meet at the train station.
Momo chooses Uwabami's Hero Office to intern at along with Itsuka Kendo from Class 1-B. They both arrive in the middle of Uwabami shooting a commercial. Itsuka mentions that she was hoping for something more heroic to then watching that, but Momo emphatically replies that garnering popularity is unavoidable as a hero and she will take any lesson Uwabami has for them. Itsuka takes note of Momo's enthusiasm  and then asks if there's anything else they can do during the commercial. Uwabami responds by admitting that the main reason she chose them as interns is that because they're both cute, making both Momo and Itsuka slightly taken back by their new mentor's response.
They later accompany Uwabami to one of her photo shoots. Itsuka mentions how she feels more like an entourage than her interns. Momo replies that there must be some kind of lesson they're missing, but Itsuka believes Momo is in denial. A few days later, Itsuka and Momo appear in a commercial for UNERI Hairspray with Uwabami. The Snake Hero shows them both a demo tape of the ad, but Momo appears to only be embarrassed by this. Uwabami decides to take them both on patrol afterward, much to their excitement.
Momo returns to school following the conclusion of her internship. When Izuku, Shoto and Tenya's run-in with the Hero Killer is brought up during class, Momo mentions that she was worried about the boys. She attends Basic Hero Training with her class afterward where the class participates in a rescue training race. While the first group prepares to go, Momo tells Kyoka she believes Izuku is at a disadvantage because of his lack of mobility. She's quickly proven wrong when Izuku jumps out to an early lead using the new mastery over his Quirk, much to Momo's shock and amazement. She watches as he maintains the lead until he trips causing him to lose.
After class, she joins her female peers inside the girl's locker room. Minoru tries to peep on them using a hole in the wall but Kyoka stops them. Momo notes how cowardly and vile Minoru's action was. She thanks Kyoka for stopping him and says they need to plug the hole immediately.
One week prior to final exams, Denki and Mina discuss how worried they are for the written portion. Momo placed first in the midterms and she says she's more than willing to help them study. Unlike them, she's much more worried about the practical portion. Kyoka, Hanta, and Mashirao ask for her help as well. Momo blushes with great pride and excitement. She gracefully says she's excited to help them and will hold a study session over the weekend at her residence. She begins monologuing about how she'll have her mother set up the great hall with tea for the study session. Her peers notice her accidental bragging, but they don't care because they know that she's so excited and bouncy that she doesn't even know she's bragging about her wealth.
They all eventually meet up at the Yaoyorozu's giant, fancy estate, where Momo helps them study. Thanks to her guidance, Denki and Mina feel they do well on the three days of written tests. The day of the practical arrives following the three days of written tests and Class 1-A meets up with many of the teachers at the central plaza of the exam arena.
The students believe they'll be fighting villain bots for the finals, so Kyoka asks Momo why so many teachers need to be present. Shota and Principal Nezu reveal that this actually won't be the case. Momo is surprised that the teachers are changing the format for the first time. Nezu explains that in order to better prepare the students for real-life encounters with villains, they will be paired off and matched up against one of the teachers. Momo and Shoto are paired up against Shota. A few days before the practical, the teachers met to discuss the change. Shota mentions that he will face Momo and Shoto to exploit their weakness since they both rely too heavily on their powerful Quirks. Back at the central plaza, all of the matchups are revealed in order. Momo and Shoto are set to face their homeroom teacher in the fourth practical battle. They will be allotted thirty minutes to either capture him or escape the battle stage through an escape gate. All teachers will wear compressed weights to give the students a handicap.
Momo waits by herself in an isolated room while the first two battles commence. Fumikage and Tsuyu manage to defeat Ectoplasm in the second battle. Momo says to herself that she's not surprised, and has a flashback of her embarrassing defeat at the hands of Fumikage before exiting the room. She meets up with Shoto in a replica city just before their exam begins. Shoto catches her daydreaming and asks if she's nervous. He admits he doesn't blame her since they're up against Shota and says not to worry because he has a plan for them to win.
Their practical battle begins as they run through the fake city. Shoto explains his plan is for Momo to create small objects so once she's unable to keep producing them they will know Shota is close by. Shoto plans to draw him in so Momo can run through the escape gate, and tells her to stay close to him until then. Momo reluctantly goes along with it since she's lost confidence in her own ability to make decisions. She begins making matryoshka dolls and praises Shoto for his quick thinking, telling him that although they were both let in on recommendations, Shoto's shown more practical skills for being a Pro-Hero. She admits that she only followed his orders in the Cavalry battle and that she was swiftly exposed as a weakling when it was her turn to fight. Shoto interrupts when he notices Momo's stopped producing the dolls. She apologizes, but it's too late as Shota has already found them both.
Momo runs away on Shoto's command, starting to panic and several indecisive thoughts run through her head. Her lack of confidence is even evident to Shota himself, who quickly catches up to her. He uses his capturing weapon to grab her arm, but she notices her Quirk isn't erased and uses it to free herself. She runs in the opposite direction back towards Shoto. She finds him hanging from a light post, restrained by Shota's capturing weapon. She apologizes but Shoto warns her that Shota is fast approaching. She begins to panic again, unable to decide whether to run or save Shoto. He asks her if she has a plan and apologizes for not asking her beforehand. Momo says it won't work since his plan failed earlier. Shoto encourages her to trust her instincts because he believes she's better at leading their team than he is. He even admits that he voted for her to be Class President because he felt she would be best at leading the class. Shoto's encouragement helps Momo believe in herself and she realizes how disgraceful she's been acting.
Shota eventually reaches them and asks if Momo's given up. She responds that she hasn't and warns Shoto to close his eyes. She throws the dolls at Shota and he hits them, triggering the flash bombs inside them. Momo uses the opening to free Shoto from his restraints and announces that she does have a plan to take advantage of Shota's weakness. They both run away from Shota as Momo explains that his Quirk has been unstable since his injuries fighting Nomu. They rush down a street as Shota attacks them again with his capturing weapon. Momo mentions that passing the exam is all a matter of timing. Shoto questions how timing is relevant if Shota can take away their Quirks at any given time. Momo thinks to herself that Shoto's wrong to believe that Shota can keep their powers erased. Just as Momo expects, Shoto's Quirk returns to him in time for him to use his Heaven-Piercing Ice Wall technique to block off Shota's pursuit of them.
Momo creates a weapon similar to Shota's using her Quirk and explains her full plan to Shoto. He agrees with her and they go through with it together. They run from behind the ice wall wearing cloaks. Shota attacks them, but the upper halves are only mannequins and a catapult was hidden under the cloak as well. Momo tries to trigger it and shoot the cloth at Shota, but she misses. Shota backs off anyway, giving her a chance to trigger it. She orders Shoto to blast his flames and explains that the weapon is made of nitinol alloy and when it's heated it returns to its original shape instantly. This traps Shota in an instant, allowing Momo and Shoto to handcuff him and pass the exam.
Shoto mentions that her plan went a bit too smoothly. Momo replies that she messed up by missing the initial trigger, and believes that Shota may have let them win. Shota explains that he was simply distancing himself from Shoto since he was still covered with a cloth, and this is what lead him directly into her trap. Shoto realizes it was a matter of timing all along and thanks Momo. She's overwhelmed with emotion and begins to cry. Shoto asks what's wrong, but she tells him it's nothing. He tells her there's a pressure point on her foot if she's feeling nauseous, and she tearfully tells him again that it's nothing.
Momo watches the remaining exams from the monitoring room. During Denki and Mina's battle with Nezu, Momo deduces that the principal is predicting his opponent's moves and planning his attacks through specific calculations using his Quirk. Momo, Tenya, Izuku, and Tsuyu are shocked when his sadistic attitude comes out during the match. Ochaco enters the room and is shocked to find that Mina and Denki fail the exam, which Momo confirms to her.
Koji and Kyoka are able to pass thanks to the former's Quirk, but everyone in the room is disgusted that he attacked Present Mic with bugs. Mezo and Toru pass as well. Momo mentions that Toru is unmatched when it comes stealth ops. Momo isn't amused to watch Minoru run from Midnight during their battle, but she's pleasantly surprised to see him pass. All Might proves to outmatch Katsuki and Izuku in their fight. Momo and the others watch in horror until Izuku carries Katsuki through the escape gate.
Class 1-A returns to homeroom class following the conclusion of finals. They're given the next day off and Shota reveals that everyone will be going to training camp in the woods over summer break. Most of Class 1-A decides to go shopping together at the Kiyashi Ward Shopping Mall to buy necessities for the forest lodge. At the shopping mall, Kyoka says that she wants to buy a duffel bag and Momo replies that she will help her look for it.
A day prior to summer break, Momo and the girls enjoy themselves at the U.A. school pool. The boys come afterward for endurance training. Momo and the girls offer to help officiate the boys swim races before they're all kicked out by Shota.
Summer break begins and Class 1-A rides a bus to a forest reserve belonging to the hero team: The Wild, Wild Pussycats. Pixie-Bob and Mandalay introduce themselves and challenge the students to reach base camp past the forest in three hours. When most of Momo's peers refuse, she and her class are forcibly thrown into Beast's Forest by Pixie-Bob's Quirk. The students are attacked by dirt monsters created by Pixie-Bob, with Momo working together with Toru, Mina, and Koji to destroy several of the beasts by creating a cannon to shoot them.
Class 1-A doesn't arrive at base camp for several more hours. Well over their time limit, Class 1-A arrives at the base camp exhausted and battered. Mandalay reveals the time limit was the expectancy for actual heroes, not the students. The Pussycats serve the student's dinner and the girls bathe in the hot springs afterward. Minoru tries to peep on them and the girls are grateful when Kota stops him.
Training begins the next day. Momo trains her Quirk by constantly eating sweets while creating dolls at the same time. Later that day, the students are tasked with cooking curry for themselves. Mina and Ochaco ask Shoto to light the fire for their oven. Momo comments that they shouldn't rely on him and they need to learn to make fires for themselves. She creates a torch lighter to light her oven. 
Following the next day of training, Momo is paired up with Yuga for a test of courage presented by the Pussycats. Minoru tries to trade partners with Yuga but he refuses. Class 1-A students traverse the forest while Class 1-B students try and scare them in the dark. Their fun event is interrupted by the arrival of the League of Villains' Vanguard Action Squad. The forest is filled with poison gas. Momo creates gas masks and rushes through the forest, handing them out to all the students. She joins up with Yosetsu so he can guide her to the students in Class 1-B. Momo leaves Yuga behind to watch over Kyoka and Toru, who have both been poisoned.
A rampaging Nomu eventually attacks Momo and Yosetsu. Momo suffers a serious head injury and she wakes up to Yosetsu carrying her while running away from the monster. Nomu is recalled by Dabi before it gets the chance to kill the students. Momo surmises that the villains have likely captured Katsuki and makes a tracking device for Yosetsu to stick to Nomu with his Quirk. 
The Vanguard Action Squad successfully captures Katsuki and escapes with most of their members. Momo is taken to the hospital and treated for her injuries. After recovering, she meets with All Might and Detective Tsukauchi in her hospital room. She tells them about the tracking device and gives them a receiver to track the signal. All Might commends her judgment and promises to handle the situation himself. 
The next day later that night, Shoto along Eijiro wait for Izuku and Momo. Izuku and Momo arrive but before Momo can speak, Tenya appears. He is angry that they are about to repeat the same mistake he made at Hosu. Despite Izuku knowing that breaking the rules is against the law, Tenya punches Izuku in the face. Tenya is angry and frustrated that they are not taking his concerns, feelings and worry into consideration; Tenya says that he doesn't want to see Izuku or any of them land up with severe injuries. Shoto tells Tenya that they will not engage the villains in combat while Eijiro states that their rescue will be covert. Momo states that she came along to accompany them all in order to prevent them from engaging in combat. Izuku tells Tenya that after failing to save Katsuki at the training camp, his gut feeling is telling him that he must save Katsuki. Tenya sees that they are determined and resolute and is cheered up by the fact that they won’t engage in combat; Tenya decides to go with them.
Momo along with Izuku, Eijiro, Tenya and Shoto travel by train to the city where Momo's tracking device detects the villain with her button beacon. After putting on disguises, they head towards the League of Villains' hideout. They continue towards the place that Momo's tracking device is detecting. After waiting for a while near the place, Momo notes that the villains have made no movements and states the possibility of Katsuki not being in the place while Tenya reminds them that if he sees any combat, then he will not hesitate to stop them.
Afterwards, Momo, Tenya, Shoto, Eijiro, and Izuku prepare to infiltrate the supposed League of Villains’ hideout. The group go to the back of the hideout and see a window. Momo acts as recon while Izuku and Eijiro see what is inside with the night-vision goggles Eijiro brought along. Suddenly, Mount Lady destroys the front of the warehouse which shocks Momo. Seeing that the Pro Heroes are at the warehouse, Momo and the group assume that All Might is with Katsuki as they are speaking and decide to head home.
Suddenly, the entire warehouse is completely destroyed by a man along with the surrounding area being significantly damaged. She was paralyzed by fear due to All For One's overwhelming presence and is unable to move. As the battle between All Might, All For One, Katsuki and the League of Villains continue, Izuku comes up with an idea and explains his plan to Momo and the group. She watches as Izuku, Eijiro, and Tenya enact the plan Izuku came up with, which allows them to rescue Katsuki. Seeing that Izuku, Eijiro, and Tenya have succeeded in rescuing Katsuki, Shoto and Momo begin escaping from the battlefield.
Shoto later phones Izuku and finds out that him and his group are at the train station. After All Might defeats All For One, Momo and Shoto meet up with Izuku and his group. They take Katsuki to a Police Station for his safety. Afterwards, Momo goes home.
Following Katsuki’s rescue and the retirement of All Might, Nezu ordered the construction of the Height Alliance, buildings to house the students, and thus protect them.
When Class 1-A is introduced to their dorms, Shota Aizawa states they must start preparing to get provisional hero licenses like they had planned to during the training camp. Before they can enter, Shota reads the riot act against Izuku, Tenya, Momo, Eijiro, and Shoto for participating in the Katsuki’s rescue, breaking the rules in the process, and the others who did nothing to stop them from doing it through the proper channels, stating that aside from Katsuki, Toru and Kyoka, he would have expelled all of them for their actions, if it weren't for All Might's sudden retirement. Shota advisesthe five who went to Kamino Ward to go through the proper procedures next time which will also restore the trust between them.
Momo and the other students explore the dorms, and she comments that her room is smaller than her closet. Later that night, after everyone arranged their luggage in their respective bedrooms, the girls of Class 1-A suggest a room showcasing competition. She checks the boys' rooms, being especially impressed by Rikido Sato bakering skills. When they check her room, everyone is surprised to see how luxurious and lavish it is but also cramped. Momo's room has a very large bed in it and with very little space because she miscalculated the space. Back in the common space on the first floor, she votes Rikido Sato the winner, solely because of his cake.
After the competition, at Ochaco's urgings, She along with Izuku, Shoto, Tenya, and Eijiro all meet outside the dorm where they find her with Tsuyu. Tsuyu apologizes for harshly doubting their plan to save Katsuki, and they apologize for worrying her and they mend their friendship.
The next day, Class 1-A begin their school life anew. In Class 1-A's room, Shota Aizawa mentions that their first objective will be earning their "Provisional Hero Licenses". To prepare for the Provincial Hero License exam, Class 1-A students will create at least two signature Super Moves that they will use in combat, with his help and that of Cementoss, Ectoplasm, and Midnight. She mentions she is having trouble performing the special move she has in mind.
The day of the licensing exam arrives and Class 1-A travels to the National Dagobah Arena. There, they meet students from Shiketsu High School and Ketsubutsu Academy High School. The exam participants all gather to hear the rules of the exam. Each student has six balls, and three targets to attach to their body. Those whose targets have been hit are disqualified. Participants need to eliminate two students to move on to the next phase of the exam.
The room in which the students are in unfolds to reveal the arena, in which there are varying environments to battle in. As the exam starts, the rest of the schools all attack U.A. at once, however, Class 1-A is able to defend themselves thanks to their ultimate moves. Momo create some shield to protect Toru, Tsuyu and herself. Yo Shindo tells his fellow classmates that he will shatter their solid defense, and uses his Vibrate Quirk on the ground, attacking with his super move Tremoring Earth that completely shatters the ground and causing members of class 1-A to disperse.
Class 1-A students get scattered, and have to defend himself from the other students while looks for his classmates. Momo regroups with Kyoka, Tsuyu and Mezo. They go to the city area and enter a building after failing to find the rest of their classmates. However, once there they fall into an ambush prepared by Saiko Intelli from Seiai Academy.
Putting Saiko's plan into action, her classmates trap the four in a room, closing it completely and sealing off Mezo and Kyoka's Quirks that are good for detecting people. Momo realizes that she and the others are dealing with highly intelligent opponents who have been able to correctly predict all of their moves thus far. Then, they incapacitate Tsuyu by cooling the hallway down excessively using the air conditioning system, causing her to start hibernating due her Frog Quirk.
Momo makes a blanket for Tsuyu to try and keep her warm. A Seiai student welds one of the doors to the hallway shut, leaving only one door for the U.A. students. Momo predicts that their opponents are behind that door and that it would be dangerous for them to try to break through. Momo considers what she can do to help with the cold air, and decides she could create some clay to block the vents. However, she realizes the foe’s plan is. Momo deduces that she adds the most uncertainty to Saiko's planning, and thus their opponents are trying to remove her from the equation.
Momo comes up with a plan. After reading her book, she creates four headphones and a large amp. Saiko readies her allies to storm the room but is surprised when her rival students counter with a high-frequency sonic wave attack, knocked out all of the Seiai students except Saiko. Class 1-A students leave the room to find Momo's plan was successful.
Saiko, hiding behind the door, grabs Momo back into the hallway and locks the doors behind her. With Momo weakened due to the strain caused by an extended usage of her Quirk, Saiko attempts to use her balls on Momo's targets. Momo creates a pair of handcuffs to restrain one of Saiko's arms, and as Saiko attacks with her other arm, Momo's friends break through the door and Tsuyu restrains Saiko's other arm with her tongue. After questioning why Momo's friends would return to help her when she surely would have been defeated, Saiko admits defeat.
Having knocked out at least enough Seiai students for all of them to pass, the four U.A. students head for the winner's waiting room..There they met up with Shoto and discover that they're the only ones who have passed so far from their class. Minutes later Izuku, Ochaco, Hanta, Katsuki, Denki and Eijiro arrive. After awhile the rest of class 1-A pass the first qualifier test.
The qualifiers are informed of the imminent start of the second part of the exam, in which the students will have to save the largest number of fake victims in a given period of time. Mezo uses his Quirk to locate victims during the second test and carry the "injured" back to safety.
Momo is in charge of leading a group of her classmates, planning the rescue operations. Momo finds a man trapped beneath debris and rushes in to help by removing the rubble, but Momo stops her because there is an imbalance in the debris. Momo creates metal pillars and Hanta Sero tapes them together, reinforcing the wall. Ochaco begins clearing out the rubble. The grandpa finds Momo, Ochaco, Hanta, and Rikido's rescue maneuvers not to be shabby. 
Due to her good work and coordination with her classmates, Momo passes the exam with 94 points, receiving her hero provisional license. All of the class 1-A get to pass the exam minus Katsuki and Shoto. Class 1-A are surprised to hear that they failed Momo Yaoyorozu offer her condolences to Shoto.
Next day to the Provisional Hero License Exam, Shota tells Class 1-A about Hero Work-Studies, hero activities done off campus, saying that it is a more formalized version of the Field Training they did with pro heroes before. Three days later, Shota Aizawa introduces Class 1-A to the people who will teach them about Hero Internships; the third-year students who rank among the top of all U.A. students known as The Big 3: Mirio Togata, Tamaki Amajiki and Nejire Hado.
The personalities of the three students leave Class 1-A confused, who get even more confused when Mirio challenges them all to a fight. At Gym Gamma, Mirio tells Class 1-A to attack him whenever and wherever they want. Momo, along her classmates, tries to fight him but thanks to his Quirk Permeation, Mirio easily defeats all students of Class 1-A.
As Class 1-A recovers, Mirio states that the reason he wanted to fight Class 1-A is to show the experience he gained from the Hero Work-Studies. Thanks to that, Mirio was able to make his Quirk more powerful and reach the top. Class 1-A applauds Mirio's speech and they realize what the work-study could do for their skills.
Weeks later, Momo see the news about the police raid at the base of Shie Hassaikai, raid in which Izuku, Eijiro, Ochaco and Tsuyu participated and in which there were some casualties. When they return to their dormitories at the school, the entirety of Class 1-A checking to make sure their intern classmates are doing okay, physically and mentally, after their mission. Momo offers to make them herbal tea to make them feel better.
Shota Aizawa announces that U.A. High School will be having a School Festival and tells Class 1-A to pick out a program to perform at the festival. Tenya Iida asks ideas from Class 1-A; but they did not reach an agreement. At Heights Alliance, the entire Class 1-A decides that their school festival program will be a live performance and dance with party space.
Next day, Kyoka decides who will be the members of the musical band: Kyoka herself will be playing the bass and be the vocalist, Katsuki will play the drums and, and Denki and Fumikage will be the guitarists. Momo Yaoyorozu suggests playing the piano, having grown fond of playing it since her etiquette training in her childhood. Kyoka Jiro approves of Momo's choice, much to Mina Ashido's disappointment who wanted to dance alongside Momo. The rest of Class A-1 are divided into the Staging team and the Dance team.
Until the festival, the Band team constantly practices under the lead of Kyoka. During a break, Momo Yaoyorozu has received special tea from her mother called Phantom Black Tea "Imperial Golden Tips". As Momo prepares to let her classmates try the tea.
On the appointed day, the performance of class 1-A ends up being a huge success.
As November comes to a close, the Wild Wild Pussycats pay a visit to Class 1-A to celebrate Ragdoll's reinstatement.
Days later, at the U.A. dorms, Momo and her classmates watches a report of a Nomu attack and was horrified as it showed Endeavor overwhelmed by the Nomu's attack. A worried Momo looked to Shoto who walked in to watch the scene of his injured father.
After Endeavor manages to defeat High End and stands up victorious, Shoto collapses to his knees, relieved his father is still alive. Momo is one of the classmates who approaches him to console him.
When Class 1-A and Class 1-B face off as part of a training exercising, Momo is placed in a team with Yuga Aoyama, Toru Hagakure and Fumikage Tokoyami, being the leader. They will compete against Class 1-B team formed by Kinoko Komori, Shihai Kuroiro, Manga Fukidashi and lead by Itsuka Kendo, in the second round of match-ups.
Before the round started, Itsuka confronts Momo and asks her about the beauty pageant. Momo replies she didn't know about it plus she had band practice. Itsuka claims that ever since their internship together her and Momo always get treated like a pair. Toru says that some fans during Class 1-A's performance kept yelling out "Yaoyorozu and Kendo". Itsuka doesn't like being lumped in with Momo because she feels her rival has a better Quirk and better grades. Itsuka has always wanted the chance to fight Momo head to head. Momo accepts her friend's challenge.
As the second round begins, Momo takes the initiative and leads her team. Fumikage send Dark Shadow to locate the opposing team, but Dark Shadow is possessed by Shihai, who manipulates the beast into striking its master. Shihai exits Dark Shadow and evades two nets created by Momo by merging with the shadows between the pipes.
Shihai sneakily takes Yuga away after diverting his rivals attention, but Fumikage with Black Fallen Angel soars past Shihai and rescues Yuga from him. Momo advises her teammates as to how they should deal with Shihai. She tells Yuga to use his Navel Laser Buffet while Fumikage flies them around. This warps the shape of the shadows and takes away all Shihai's hiding spots.
After foiling the 1-B teams' initial plan, Momo declares that even the most unexpected circumstances are within her expectations. Right as she says that however, a mushroom sprouts on her nose. Kinoko uses her Quirk to cover everything in Mushrooms, hindering the movement of Momo’s team by growing mushrooms all over their bodies.
With Kinoko's part of the plan now in action, Momo yells out to her 1-A team to keep calm and regroup but Manga quickly uses his Quirk, and a large, wall-like string of Katakana suddenly appears, cutting Momo off from the rest of her team. Itsuka planned on isolating Momo to cut the brain off of her team. With Momo separated from her team, Itsuka attacks her with an enlarged palm thrust. Momo tries to block it with a dense shield but she's knocked back by Itsuka's Big Fists Itsuka barrages Momo enlarged fists of fury.
Momo believes that she isn't superior to Itsuka, but refuses to submit and resolves to earn the respect she's been given. Remembering Itsuka’s compliments and lamentations, Momo finds new resolve to win the fight. Momo creates a cannon mid-fight, much to Itsuka's surprise, and fires the cannon over the wall. However, Itsuka lands a powerful hit with her Double Jumbo Fist. After this, Momo creates a rope.
Dark Shadow grabs Toru and flies up to the bag that Momo fired, which has “Yaoyorozu's Lucky Bag” written on it. Inside he finds ethanol to get rid of the mushrooms and infrared goggles. With ethanol, Fumikage and Toru manage to prevent them from growing mushrooms through the body. And with the help of infrared goggles from Momo’s bag, Fumikage locates the Class 1-B students but was defeated due to a fungus that Kinoko caused to grow mushrooms in his windpipe.
Meanwhile Toru locates Manga and attacks him. She is about to defeat him, but in that moment Kendo appears and captures her in her giant grip. Momo roped Itsuka to herself while she was still attached to the cannon. Itsuka knocked her unconscious, but now she can barely move because of the great weight she carries. Class 1-B comes out victorious with a 4-0 in the end of the second round of match-ups, but Itsuka doesn't feel victorious since Momo was always one step ahead.
Before the third round started. Itsuka accompanies Momo to the infirmary while looking on concerned. After a quick recovery, Momo joins her classmates to watch the rest of the Joint Training Battle.
Afterwards, it’s revealed that Class 1-A won the entire exercise and a relieved Momo celebrates their outstanding victory over Class 1-B. Later, classes 1-A and B hanging out together after the exercise, showing that there are no hard feelings. Momo spends time talking to Kendo.