Surprisingly Improved Sequel: Aliens Ate My Homework' is a great, stand-alone young adult sci-fi story. After finishing it, you might not even realize there are three more books. But those three books introduce the ultimate story arc of BKR's master plan, and adds in a lot of character development and surprising revelations that manage to outshine the original story.
Ho Yay: Grakker and Snout share a room, become very emotional when the other gets hurt, and at one point Snout (who does have telepathic powers) mentions that he is "bonded" to Grakker and is thus able to pinpoint his location. It becomes even more obvious when one realizes that they are blatant Kirk/Spock expies.