Kids are undoubtedly going to be GLAD that you're back in school -- and you know how teens are -- they're going to want to know what happened. Just tell them that 1) you'd rather not talk about it OR 2) you can't remember. Tell them that they can probably get an old newspaper and read about it in there.
It might be kind of fun though to be the center of attention for awhile.

They'll probably all pat you on the back, and say they're glad to see that you're back and you're okay! Make sure they sign your cast if you have one. You can keep that as a "reminder" -- years from now you can look at that thing and remember how close you came.
Don't be nervous ~ be grateful that you made it thru -- and that the kids will be glad to see you!! I'm SURE they will be. The word has gotten around that you were in ICU, etc. So I'm sure they knew how badly you were hurt. I'm also sure that you must have gotten some prayers from kids that you didn't expect them from. So enjoy your day back! God bless you and I'm SOOO glad you're ok!!!

Hugs, Lee