Chapter 11 was about when Mike and Crash were having a food fight and when one of the teachers caught the food fight, they were sent to the principals office. The principal gave them one warning and then sent them back to class. After that they went on to the football game and then found out that Penn was doing cheer leading.
Chapter 12 was about when Mike and Crash were at Crash's house and had sundaes and pizza. When they were eating, they were talking about football.
Chapter 13 was about when Crash's mom and dad came home looking exausted. Abby had a lot of energy when they came home. Crash's parents made cheese steakes. Crash mentions to his parents about Penn doing cheer leading and the parents were laughing about that. As you can see this is a summary of chapter 13.