I'm bringing this up now because
1. you'll need time to get it done, and
2. I know we teachers need lots of lead time to prepare.
But one of the best gifts children can present to their mothers is the classic silhouette. Preparation is easy. All you need is black and white construction paper, and a lamp with a bared light bulb.
I found that doing this during center time worked best for me. In fact, the students often stopped what they were doing to watch me trace the outline of their friends on the black paper. I'd normally do 1-2 a day, then take them home to cut out while I watched TV. I then mounted each one on the white paper, and used tissue paper to wrap them for presentation. The children would make cards to go with their gifts.
Yes, it's time-consuming, especially the time it takes to carefully cut them out. But the end results are well worth it. And mothers were always telling me later on that they'd had the picture framed, and hung it on the wall in their homes.
This is definitely a treasure worth keeping.