Sweet little metal box full of... mouses! Starting from this diagram of Mmmcrafts, you will be able to build from felt and fabric this house to hosting some small rodents that your children may carry wherever they want. Moreover, it would be a great corner to save their first loose teeth and change them to the Tooth Fairy for small treasures.
1st birthday keepsake for baby to decorate their room of finger prints of family and friends attending the party. Could also use for reveal party and have pink and blue ink to indicate their vote on whether it's a boy or girl.