The baking soda + Kool Aid + water mixture had a surprise effect and began fizzing and "fuzzing" (as Harrison put it) when the water was poured in. This was a treat for the kids, as well as me because I didn't even think about the Kool Aid and the baking soda having that reaction when mixed together.
All mixtures were the same consistency and all safe if a child decided to try the yummy smelling paint (no one did so that wasn't even an issue). I also tried one of the multi-ingredient recipes I had found on Pinterest and it had the exact same consistency as flour, Kool Aid, and water mixed together. In my opinion, I find it unnecessary to use a more complicated recipe when using only flour works just as well. I had the kids use different colors of construction paper (I would normally use card stock for a project like this but didn't have any other paper besides construction paper) and I think that played a part in how the paint dried.
As soon as the kids began painting and the mixture hit the construction paper, it seemed to melt into the paper. Not in a the color just disappears kind of melt, but in a melting and blending with the paper kind of way. Putting the painted paper in the hot sun seemed to "cook" the paint in a way. After a few minutes in the hot sun (it was 95 degrees that day) the flour, Kool Aid, water mixture started bubbling. The kids put A LOT of paint on each piece of paper yet it only took an hour to completely dry out in the sun. This seems to dry quite quickly compared to the kids usual paintings using Crayola washable tempera paint.
One of my worries was how the Kool Aid paint mixture would wash out of clothes. Kool Aid has a way of staining things (clothes, kids tables, counters, carpets, just to name a few I've had experience with in my adventures of using it for dying rice and pasta). However, I am pleased to report that it washed out just fine of my kid's clothes, in addition to the kid's table, our floor, and rug. I was very pleased with how this experiment turned out and have plans to do it again later this week. This time we will be trying it with cardstock and as outdoor paints. Hopefully we'll have the same good results!