every year I give my girls's teachers a small box of hand crafted thank you notes. I make them myself and I have been complemented over the years.
I enjoy making birthday cards, thank you cards, congratulation cards. I buy the gift box and put the cards in that. The teachers have loved them because they can use them as they wish.
I use Stampin Up rubber stamps for the crafting but Michaels Arts and Crafts has a nice selection of stamps and markers. Once you have the materials you are set and you make many cards. The teachers like it because it is a unique gift.