A janitor is among the injured after a food fight by seniors on their last day at an Ann Arbor high school.

Spokeswoman Liz Margolis says the food fight Friday at Skyline High School involved water, baby oil and shaving cream. A janitor who slipped was taken to a hospital. Margolis says several students had minor injuries from slipping on the floor. The pranks this week included putting the school for sale on Craigslist.org and releasing bouncy balls throughout the building.

Those were viewed as harmless. But Margolis says it's ``really disappointing'' that seniors chose a food fight on their last day.