Get a helmet, PLEASE. My 9 yr old son did an endo on his bike last week. He landed on his head and his helmet was in two pieces, but he got up and walked away (crying) but alive!!! They wear helmets for sledding and Skiing also.
They even have orange ones that might match your bike. Here's one
http://www.thebellstore.com/Other/bellbicycle/Citi.html