Bart pulls down on the remote lever when demonstrating his first prank on Lassen. When he actually pulls the prank, he pushes forward on the lever. It is done correctly the first time, since the car moves forward both times.
The main plot of the episode centers around Bart's new teacher, and many scenes are at school or in the classroom. However, early in the episode Marge chastises Homer for failing to book a camp site in advance, explaining that "Labor Day is just a week away". Unless all the kids featured in the episode at school (including Lisa) are in summer school for the whole episode, then the events would all be taking place during August because of this line, and therefore Bart would be on summer vacation.