The jellybean experiment is about making friends. Calvin is new in school and while he isn't trying to "fit in" per se, he is trying to make friends. His creative and wacky use of jellybeans is funny and inventive. When he tells Danny about his dad being a spy, Danny learns inadvertently from Calvin's mom that their dad abandoned the family and works as a truck driver. It seems that Calvin is in denial over his dad's actions. Calvin does not appear to be covering for his dad when he tells Danny he is a spy, he truly believes his dad is a spy that purposefully tells others he is a truck driver to cover up his covert activities. This isn't resolved in this book. Perhaps in book two the parents will divorce forcing Calvin to face the situation.
Danny's character is not sure about Calvin, but he is interested in him because he's different. Danny seems to be deciding throughout the story whether or not he wants to be Calvin's friend. Calvin likes to poke fun at their crabby teacher and get away with breaking rules that appeals to Danny at times and scares him at other times. Calvin tries a bit too hard to be the class clown using shenanigans as a way to make friends. At first I wasn't sure if Calvin was rebellious, but he pulls back when it matters to peers such as during the report presentation. There is a subtle message about tolerance and accepting others for who they are inside and not going by appearances.
The title of the book is a bit misleading and the illustrations don't add to the text. Danny doodles because he wants to be a cartoonist. I kept waiting for more to happen with this. In Marissa Moss's Max series the two boys come up with a comic strip that has erasers that are aliens that come to earth. Nothing like that happens with the doodles and they are not worked into the plot. While I enjoyed this story and the writing is good with fun wordplays, what stands out the most for me is that it is nice and short for the student who does not love to read.