Why do bubbles always come in the shape of a circle? This might be a good question to ask your kids the next time they want to play with bubbles outside. For instance, if you used something other than the bubble wand they give you, could you make a different shaped bubble? Asking questions like these about the world can never begin too early, and getting kids to make hypotheses and to experiment is the foundation of science.
So have your kids explore that question while they rifle through your kitchen drawers looking for bubble-making implements. Encourage them to think about which utensils would make what kind of shaped bubble and which wouldn't make a bubble at all. Then pour some soap into a tray with water and experiment to see if the kids are right!