Mikey Blumberg is a member of the Recess gang. He is the most sensitive and most forgiving in the group. He is also the best poet in fourth grade, coming up with poems at any times.
Many think that Mikey is a bully just because of his height, but, as once described by T.J. Detweiler, "he wouldn't hurt a fly". There is a hidden agenda about him, and that is his love for Bonky the Dinosaur. Bonky is a dinosaur in ways similar to Barney the Dinosaur and is loved by the kindergartners. In the episode "Bonky Fever", it is shown that and the rest of the gang try to stop it. At his birthday party, once the gang thinks he has stopped the Bonky nonsense they all see a party full of Bonky things and toys. Thanks to the gang, he finds out it is his mother in a Bonky costume and he does eventually stop showing his love for Bonky.
Mikey does have another hidden agenda which is his singing voice. He believes he cannot sing anywhere apart from the bathroom. Until Principal Prickly and Miss Finster get him a private music teacher who helps him feel confident in singing other places. She trains him for the Spring Fling, which he would succeed in and do everyone proud.
Recess: School's Out
On the last day of school, Mikey, Spinelli, Vince, and Gus give out ice cream to the other students using Mikey's catapult, much to Ms. Finster's chagrin. Just when T.J. talks about summer plans, Vince, Spinelli, Gus, and Gretchen mention going to different camps the next morning. Mikey, on the other hand, is going to a singing training center. A disappointed T.J. accompanies them to see them off. As Mikey gets on his bus, he sings "Bon Voyage, T.J.", causing the windows to crack slightly.
A couple days later, after T.J. notices strange activity going on at the school, and witnesses Principal Prickly get dematerialized and transported into the school, he and a reluctant Becky pick up Mikey and the others. The six sneak a box of documents from the school, finding only useless papers inside, and see a person identical to Prickly. Thinking that T.J. tricked them just to get them back, they proceed to return to their camps, but then see a device come out of the school roof and fire a green laser beam, causing Mikey to faint, reawakening in T.J.'s backyard, inside a wheelbarrow.
T.J. comes up with a plan to get proof about the activity at the school, watching it until something happens, and then catching the bad guys in the act, as well as bringing his friends back to their camps in the morning, and meeting up again at night. Watching the school from the treehouse, they reflect on their memories of past summers, to which Mikey remembers the "John Jacob Jingleheimer Schmidt" song Becky taught them after kindergarten, and sings the song, with T.J., then Vince, then Spinelli, Gretchen, and Gus joining in. The next day, T.J. finds Prickly's golf pants in the school dumpster while hiding from the guards. Examining the pants, they find a note that says "Help Me!" in the pocket, which Mikey concludes is a desperate cry for help, leading them to go to the school to save Prickly, with Mikey throwing a grappling hook to the second floor window, that they use to climb in.
Inside, they go into the air vents, following them to the auditorium, which has been converted into a laboratory, and witness the device from the other day being tested before malfunctioning. Mikey then feels a need to belch; unable to suppress it, he lets it out, causing the ringleader of the operation, Phillium Benedict, to become aware of their presence, firmly expecting him to say "Excuse me." The gang's combined weight causes the vent's supports to break, and the vent falls down, resulting in the six of them tumbling out. Benedict then shouts for the guards to capture the trespassers, and while the others escape, T.J. is not so lucky, and he is imprisoned along with Prickly. The five of them go to the police station and explain the situation to the cops, who simply laugh at them, much to their disgust.
Back in T.J.'s backyard, they look through the documents again, trying to find more information about what Benedict is up to. Spinelli gets her hands on a date book that speaks of lunar perigee, leading Gretchen to explain what it means. Soon after, T.J. contacts them on his walkie-talkie after discovering Benedict's intention to get rid of summer vacation, causing Mikey to scream "Noooo!", before Kojak takes it from him. Knowing they can't stop Benedict alone, the five go to Becky at Floppy Burger, who refuses to help them or T.J., until Mikey convinces her to by saying that he needs her. As they go to the camps to rally the other students, Becky is impressed and amazed that her brother stumbled upon an evil plot, while Mikey helps himself to some of the ketchup, making Becky snap at him. After some setbacks, Gus steps in to be the students' commanding officer, and concocts a plan to get into the school and stop Benedict.
Mikey climbs onto a stepladder and sings Luciano Pavarotti's Nessun Dorma, getting the guards' attention. The guards' boss orders him to scram, then sends his men to try and get rid of Mikey, only for them to fall into a hole that the Diggers dug up on the other side of the bushes. Gus, Vince, Spinelli, Gretchen, and the Ashleys sneak past the guards and enter the school while they're not looking. As Mikey continues singing, the boss guard, unable to get hold of his men, attempts to get rid of Mikey himself, but falls into the hole as well. Mikey then rejoins Gretchen, Gus, Vince, and Spinelli inside, where they reunite with T.J., along with Prickly, then head to the auditorium to confront Benedict. After futilely trying to convince him to stop his scheme, Benedict lectures the students about his motives and how countries with wintry climates have higher test scores.
Despite T.J. pointing out the flaws in his plan, Benedict is still determined to go on with it. At the last second, Ms. Finster bursts in, along with the other teachers, leading to a showdown, during which, Mikey and a few other kids use his catapult to fire water balloons at the guards. Ultimately, they successfully thwart Benedict's scheme by destroying the tractor beam with T.J.'s baseball. As Benedict and his goons are arrested, the numerous students, T.J. and his friends included, are shown celebrating with their families. Mikey and the rest of T.J.'s friends have decided to just enjoy their summer together and that they have plenty of time to get ready for their futures. T.J. pays Prickly a visit to say thanks, then the six of them go off to the pond.
T.J. is good friends with Mikey. In "The Break-up", T.J. says he "appreciates his insane spiritual gifts". However, he is sometimes embarrassed by Mikey's behavior. In "Tucked in Mikey", after Mikey read a poem inspired by Menlo, T.J. claimed, "for once, it didn't embarrass me". He also was a little embarrassed at Mikey's comment that the 5th and 6th grader's club was a "rainbow hug of togetherness". But, T.J. respects Mikey despite his behavior, as seen at the end of "Rumor Mill".
Although the status of their friendship is not seen very much, it's obvious that Gretchen and Mikey are good friends.
Mikey looks up to Vince, which is the focus of the episode "Copycat Kid". Mikey wishes he could be "cool" like Vince and be sporty (and was quite capable of shooting baskets in the episode) until Vince copies him. In the end, Mikey realizes the value of himself as an individual. The two remain good friends afterward.
Mikey and Spinelli are polar opposites. Mikey is large and peaceful, while Spinelli is small and more violent. Mikey's sincerity and calm demeanor sometimes get in the way with Spinelli's attitude ("Gus' Last Stand", "Rumor Mill") The two share a rare moment of friendship in the episode "Dance Lessons", where Spinelli puts aside her tough attitude for Mikey's sake. She also was ready to defend Mikey when Randall made jokes about him in "Stand Up Randall", which Mikey appreciated but said it was not necessary.
Mikey is better friends with Gus than any of the other members. The two are often seen taking the same side on things (Recess: Taking the Fifth Grade, "The Candidates"). They have offended each other occasionally ("The Break-up", "Germ Warfare") but were quick to forgive one another.
- His singing voice is that of the late Robert Goulet.
- Mikey is the only member of the main six whose birthday has been celebrated in an episode, "Bonky Fever". Gretchen mentions her birthday party in "The Girl Was Trouble", however, it was only a flashback.
- Mikey is based on Paul Germain's friend back in elementary school.
- According to "To Finster with Love", Mikey weighs 110 pounds.
- Mikey has had the second most episodes focused on him out of the entire cast.