What are some good icebreakers and attention grabbers for summer camp (class)?

Hello, I am teaching a summer camp class (Nature) and I would like some ideas on how to introduce myself to the campers and have them introduce themselves to each other . I dont have any really good ideas. I will be teaching all age levels from 4 up to 14 years old (in different classes of course) but I would love your input. Teachers, Camp counselors, anyone with experience with working with children.