Bubble shapes

I've seen a lot of ideas for bubble activities from other people over the last few weeks and with some nice weather I thought we could give our own a go. Both my boys love chasing bubbles around the garden and popping them, so I hoped this would entertain them.

Small boy blowing bubbles on the table

We started blowing bubbles with a straw onto the table (with a little bubble mix spread on it, then the straw dipped into a container of bubble solution before blowing). We used commercially made bubble solution on our glass outdoor table. We talked about the shapes we made - bubbles floating in the air are spheres (a word my son learnt a couple of months ago) i.e. ball-shaped, but those on the table form half a ball. I introduced him to the word 'hemisphere', and he had fun for ages blowing hemispheres and popping them. 

We then had a go at blowing another bubble inside the first one. This in theory works because the first bubble doesn't pop when you insert a bubble mix-coated straw and then blow a new bubble, it just expands a little as the new bubble is blown inside. It has to be said that we didn't have great success with this.  The inner bubbles mostly moved to the side and fused to the original bubble very quickly. Still, we had fun and I managed to make a bubble with a bubble inside eventually! My son enjoyed blowing multiple bubbles together and then popping them one at a time and watching the shape change, although I was a little disappointed that we'd not managed something more impressive!

Hoping for square bubbles

A bit later on, we made our own bubble wands. We bent pipe cleaners into various shapes to experiment with the shapes of bubbles they would produce. We attached them to straws by poking the ends inside, but they weren't very secure and we had to improve some of them by adding an elastic band - in hindsight I can think of better ways to secure the wands to something more solid e.g. using tape to attach to a lolly stick or twig.

Selection of bubble wands

I asked my son to predict what shape of bubble the different wands would produce - we started with a round one which he correctly guessed would make spherical bubbles. Then I asked about the square one, and he guessed square bubbles. I asked him whether they would be flat, and he decided they would be cubes. So we tested the bubble wand and it made spherical bubbles! He was amazed that they were still spheres. It didn't stop him predicting that a star-shaped wand would make star-shaped bubbles, and then finding that it too made spherical ones.  He was right that a shape with two separated ovals made two bubbles, and these were spherical too.  Bubbles will always form spheres due to surface tension which means the bubbles form the shape which has the smallest surface area possible for the amount of air inside.

All spheres!

We had lots of fun blowing bubbles, even if they were all spheres.  My 3 year old and his little brother also enjoyed chasing and popping them for a long time!  Next door's cat even came to join in.

Triple bubble (plus a few extras at the edge)

The next day, my son asked to blow bubbles on the table again.  I decided we should try it a little differently and found a melamine plate with a very smooth and shiny surface.  I coated it in a little bubble mix and then we blew bubbles onto it with a straw.  This worked much better, with us getting lots of hemispherical bubbles inside each other!  Maybe the outdoor table wasn't clean or smooth enough for it to work well the previous day.  My son enjoyed blowing individual bubbles off the plate and watching them change from being hemispheres to spheres as they flew away.  Blowing bubbles is definitely a winning activity, and there was a little bit of science thrown in too!