Is there a cheat on sims 2 to do homework?

The simplest way to do this is to enter build mode and use the sledgehammer tool to delete your child's homework. The game deletes the homework when it's completed, so by manually deleting it you trick the game into thinking it's done. This also works for the mailbox, so you can avoid bills. However, if you use the boolprop cheats I wouldn't recommend deleting your mailbox -- there are a lot of cheat options which can only be activated by shift+clicking on it.