Thursday, October 09, 2008

The Solquid

Ever wonder what to do with all those boxes of cornstarch you have just laying around? Try making cornstarch feelies! I highly recommend it. We've done it several times on a small scale, just enough to play with in your hands. I've wanted to do enough to walk on for a long time. I was wanting to fill a kiddie pool with the stuff, but after doing a bit of calculation, I realized that it would take like 100 or so boxes. Not too cost effective. However I did blow 13 boxes at once here. It was great fun!

The cool thing about cornstarch feelies is that it really isn't a solid, but it's a weird kind of liquid. See, it's a surface tension thing. As long as you hit it fast, it feels solid. You can run and jump on it. But the second you stop moving, you sink into it like a liquid. When you roll it around in your hands, it will roll up like a ball, and it feels really solid. As soon as you stop rolling it, it runs all our of your hand just like any other liquid.

The formula is about 1 part water to 1.75 part cornstarch (give or take a little). That's about 1 2/3 cup water per 1 lb box of cornstarch. It does seem to dry out pretty quickly as you play with it, so you'll have to add a little water as you go. Give it a try! We love it. Oh, and here's a hint: A box of cornstarch at Shop -n- Save will run you about $1.40, but you can get one at Wal-Mart for $0.84. I haven't checked the Aldi, Save-a-Lot type stores yet.

Unfortunately, it was getting dark as we were doing this, so some of the video is pretty dark, and you can't see it so well on this little window.


lizS said...

that looks kinda cool. we will have to try that sometime!

Becca said...

When I taught preschool, we called it "Oobleck". Because that is what the kids said when they touched it. If we made it on a day when a new observer (college kids doing reports or parents) were there it was fun to assign them that area...and then watch them touch it. Clean up is awesome too, when it dries it is just cornstarch again. Looks like you had fun.

timpani76 said...

Oh, I don't know if I'm brave enought to try this yet. I'm afraid my kids would eat it!

The Marinator said...

Ooh fun! I remember doing that kind of stuff when I was younger, but I forgot about it til now. It's a great science object lesson. T - they can eat it. You put cornstarch in gravy and stuff. Just have them wash their hands before they put their grubby fingers inside and they should be ok. (Unless it's an allergy thing...but then you wouldn't let them touch it at all anyway...hmm..)

Dana Cheryl said...

I've found some great videso on youtube of this stuff. There's one video that got a swimming pool size tank full of the stuff. People are walking around on it and doing jumping jacks. It looks like a lot of fun!