I'd like to "gift" a Few High School Kids on My Bus..?

I am a driver also. I would advise against this. My suggestion would be go to the dollar store and get a couple bags of dum dum pops (usually 24 or so in a bag for $1. Give each and every kid one. If you would like you can give those ten a little extra but the last thing you need is to be seen as playing favorites. I have had this problem because of the same things you mentioned and those kids that don't acknowledge you probably have the parents who would be the first to complain.