Hi Denise,
The week sounds like lots of fun! And understand the challenge with the little gifts. HIgh school age is a little tough for little gifts. (What they think is cool or not cool -- hard to keep up, right!) Maybe school stickers for cars? Or, maybe consider using the money that you would spend on gifts for another kind of treat -- a guest speaker, another food event (pizza party, taco bar in the cafeteria)?
I am the Co President for the Parent Organization at our local Catholic High School. Every year we try and plan fun event/gifts for the kids. We usually do an ice cream social one day, a chocolate bar another day and so on for the week. Anyone have any ideas for 9-12 graders as a small gift during the week. We have tried pencils, pens, rulers and we find more in the garbage then go home.