Its programming allows it to obey whatever people want from it (like doing homework) but it can easily get abused.
Johnny soon made him get him a bunch of things (abusing the robot): a hot tub, 6 flat-screen TV's, sausages and zoo animals for his own private petting zoo which Homework Buddy was actually stealing from places around the city. The Test family decided to to get rid of it: however, since it ran on lithium oxide batteries that, if removed, release a toxic gas that would kill them, they just returned everything it stole so they wouldn't connect it to them.
Afterwords, the Test family gave the robot to Mrs. Majekowski, the old lady who lived in their neighborhood as a way of apologizing for taking cookies from her and so she has some help around her house. Unfortunately, Homework Buddy still continued its stealing spree.