After working with kids for 30+ years I've learned that you have to be very careful what you say to them. They don't understand a lot of idioms and they tend to take things that you say literally. It causes worry and concern for adults, but it's always hilarious. Here's a true story from one of the other principals.
A father came in to school to get an early dismissal to take his 7th grade son to the doctor. The principal called the boy down to the office. When she saw him she told him to go get his jacket for an early dismissal. The boy left the office and when 10 minutes passed and he hadn't returned everyone started to get worried. Fifteen minutes passed; no boy. Twenty minutes and everyone start to look for him.
Shortly after they searched everywhere in the building the boy walked into the office. When the principal asked where he had been he replied, "You told me to get my jacket. I didn't wear a jacket today. So I went home and got it."
a 7th grader is 13 years old...!