[Image]  We have a large mound of dirt in our yard, and I thought it might be the perfect place to try out our volcanoes, as I didn't want to repeat the inside explosion. Desert Girl was happy to dig.

[Image] Desert Boy was given the task of burying some plastic bottles, aka magma chambers.

[Image]  Then his friend Neto came over to help with the volcano eruption. I mixed a little food coloring in with the vinegar to give it some extra oomph.

[Image]  I never did find the exact proportions of baking soda to vinegar we were supposed to be using, so I just guessed. I also had the kids make a "forest" on the hill.

[Image]  Eruption time! Looks like the forest was spared.

[Image] That was so much fun we had to do it again and again until we had used up all the baking soda and vinegar.

[Image]  A few days later, after resupplying, Ava came over and we had to show her volcano hill.

[Image]  The kids were looking forward to what would happen.

[Image]  Ava and Desert Girl don't look so sure about the eruption, but Desert Boy is clearly enjoying the mess.

[Image] We kept going with more explosions. We are still trying to perfect the technique and see a two-foot high explosion. So if you have any ideas, let us know. In the meantime, we'll keep experimenting. It's nice to be outdoors!