A toy that is educational and free is always a winner!  If that sounds too good to be true, check out this idea from Sue at Bhoomplay that falls squarely into both categories.  Using recycled supplies, she created this clever, interactive jellyfish in a bottle!  As you move and shake the bottle, the jellyfish “swims” around inside.  Your kiddos will get hour of entertainment out of things that were originally headed for the garbage, and you get a great opportunity for a science lesson.  Everybody wins!  [how to make a jellyfish bottle]

Project estimate:

• Plastic bag, on hand
• Thread, on hand
• Bottle, on hand
• Water, on hand
• Food coloring, on hand

Total:  Free