So, I don't know if it's just a Utah thing but every spring at the Hindu Temple in Spanish Fork has a "Colors Festival" which is more commonly known as Holi. Essentially you all gather at the gorgeous temple and throw colored cornstarch at each other and all over while some awesome music/chants are played live. You also get to go through the temple. It's very fun!
Awesome, yeah?! So I saw something on Pinterest where they did the whole baking soda and vinegar thing out of plastic bottle but they put food coloring in, which seemed a million times more fun to me! One day me, 2 of my step brothers, and my sister were doing all sorts of weird things with vinegar and I had an AHA moment. We filled up big glass mixing bowls with baking soda (like a layer across the bottom) and then had small bowls with vinegar and different food colors in each one. We went ghetto style and just used straws to get vinegar on the end and drip it into the baking soda. Let me just say the 4 of us had fun for a solid 45 minutes.
It was really interesting how differently it looked when you poured a little in, or a bit more (by holding the top of the straw while its in the vinegar). The blue bowl on the bottom left was after we we're done playing we dumped all the colors into the bowl and then stirred parts and just played some more. The best part... it was really NOT messy. If you have a light colored table I would recommend investing in a dollar store table cloth for crafts and throw that down ( we are using food dye). We didn't have any trouble just wiping it off with what we usually clean the table with as soon as we were done. It was just small drips from moving the straw from the vinegar to the big bowl.
If you are going to do this and maybe plan a bit in advance I would use some sort of little squirt bottles. Catchup style ones would be cool, but so would the little hair water bottles (ya know the ones that squirt like cleaner bottles from the travel section at Walmart or the dollar store?) Maybe do one or two of each?!
If you try it, come back and tell me if you (or your kids ha) liked it, what you changed, etc.