For in-laws... I know this is meant to be given as a gift for a wedding but I think it would be ok to give anytime. A Dad (or Mom) want to know that they have done a good job parenting and hardly ever hear it said.
...this is totally genius. And not just for kids! This is what happens when you microwave a bar of Ivory soap! Then you can tear it up, color it, and mold it into shapes! It's not wet and messy, either! This is awesome!
I really like the idea of making the holidays more about spending time together than about "getting stuff." Activities include: Make hot chocolate and stir with candy canes, Watch a christmas movie and eat popcorn, Go out for a Christmas treat, Do something nice for someone, Drive around and look for Christmas lights