Detectives in Togas 2

I am reading the book Detectives in Togas. It is pretty good so far, but I'm not very far along yet. It is about young Roman boys who attend a private Roman school called Xanthos School. Their teacher, Xanthos owns the school. They don't call him Xanthos though, they call him Xanippus, secretly of course. The boys are mischievous, and one day when they all should be reciting their Greek words, Rufus, a boy who attends the school, writes on the chalk board, Caius is a dumbbell. This causes a lot of ruckus and Caius and Rufus start fighting. Both Caius and Rufus get into trouble, and Rufus is told he can never come back to Xanthos School.