I just love fun tutorials and things you can do with your children. Parole de pate's blog site has a lovely and fun project for a singing button. My goodness, that takes me way back. I remember making them from real buttons and seeing this tutorial using polymer clay just added another wonderful dimension.
The blog is in French but you can always use a translation site to get it in your language.
So go have fun! Make a fun toy...and if it's just for yourself...well, I won't tell because I think I'll make one just for me too!!!