In detention, the green chalk board shows a sentence written multiple times (in classic school-type punishment): "I will not question the gym teacher's authority ever again." (Coach Tugnut is temporarily in charge of the school while most other administrators are absent for various reasons.)
The background music used in the scene where Ren, Louis, and Chloe put together the display case is the same background music used in Spyro: Year of the Dragon, specifically the level "Harbor Speedway".