Background
Chōji was born into the Akimichi clan, and is slated to become the Sixteenth Head of the Akimichi after his father, Chōza. When Chōji was younger, he was often put down for not being good at a child's game called "Ninja", which appears to be a cross between tagand hide and seek, often employing the use of shurikenmade out of cardboard and sticks. His peers would always berate him, telling him that any team that he was on was bound to lose. One day, they simply refused to let him play at all. However, Shikamaru Nara stuck up for him, saying that the teams would be uneven if Chōji didn't join them. This gave Chōji a little hope, although, in the end, they still refused to let him play.
Chōji and his father were later seen talking on the roof of a building while Chōji was still upset over the way he was treated by the other children, saying the Akimichi were all fat and stupid. Comforting him, his father told him that few people have a heart as kind and caring as his, and one day he would meet someone who would see that in him and respect him for it, and that eventually they would be the best of friends. Soon after, Shikamaru arrived. Chōji recognised him as the one who had defended him earlier, and asked Shikamaru why he wasn't playing the game, to which Shikamaru responded that it was too troublesome. He then told Chōji that he liked to come up there to watch the clouds and that Chōji happened to be sitting in his spot. Chōji moved over to give him space. Shikamaru proceeded to lie down before telling Chōji that he should watch the clouds with him. This delighted Chōji, and he eagerly asked Shikamaru if he wanted to eat some snacks that he had brought. Shikamaru took him up on the offer, causing Chōji to be overjoyed, and then Shikamaru said "This is the best, watching clouds and eating chips". From that day on, the two became best friends.
During Chōji's time at the Academy, he was often caught eating in class otherwise getting into trouble along with fellow deviants Shikamaru, Kiba Inuzuka, and Naruto Uzumaki. Together, these four would cut class or otherwise be testing the patience of Iruka Umino, their Academy teacher. During the Search for Tsunade, when Naruto was struggling to learn the second step of training for the Rasengan, he recalled how once, during his days in the Academy, he, along with Shikamaru, Kiba, and Naruto were held back in class, and lectured about their all around lack in concentration — in Chōji's case, he was thinking more about food than about doing his school work. During the arc involving the trap master Gennō from the long-gone Kagerō Village, it was mentioned how Shikamaru, Chōji, Kiba, and Naruto would skip class together and hang out at the kunai practice course, which was situated under the Academy, to hide from Iruka.