What should i teach little kids about horses? (re-post)?

i was volunteered to teach my brother's cub scout group about horses. they're all about 8 years old (yeah lucky me, right?!) i'm not sure what to teach them about and make it interesting too so that they won't be bored out of their little minds! I know almost everything about horses so its not like im scrambling to teach myself stuff. What can i do to make this a fun learning experience. oh and i'm not allowed to let them ride the horse, but grooming and stuff is okay.