Button animals! Would be adorable gift for a baby shower or decoration for a little one's room. Cute! Teddy Bear, Cat, Dog, etc. Even flowers or butterflies. Could use cookie cutter to trace shape onto felt. Cut out, glue buttons on. Apply to frame.
If you need a super simple volcano recipe, it doesn't get much easier than this. Prep is about 3 minutes, and there is no clean up necessary. Easy Baking Soda and Vinegar Volcano Eruption for Kids by Preschool Inspirations