Don't Eat Your Boogers (You'll Turn Green): Boys Will Be Boys Series, Book 1 (Unabridged‪)‬

Goober McGee has a bad habit. He eats his boogers! His older brother, Sludge, warns him that he could come down with a case of Boogeritis. Goober thinks Sludge is pulling his leg. Then one day, he wakes up, and he's green - everywhere! Goober begins to panic. Was Sludge really right? Will he have to go to school like this? How does he get rid of it? 

In the process of getting well again, Goober learns to try new foods, becomes a role model for his peers, and, most importantly, promises to never eat his boogers again.