The life-changing magic of adding water to cornstarch

The snow wasn’t stopping and the kids had already played outside. They’d also played Barbies and LEGO, read books and played with the container of Moon Sand I keep hidden away for “special” occasions. Lunch was hours away, or is that just how it felt?

The kids needed another activity, so our seven-year-old daughter asked if we could make a batch of “oobleck.” I had no idea what she meant until she described it.

“Oh, you mean ‘magic mud,’” I corrected her, smiling at the memory of my mom making magic mud for me and my sister when we were kids. It was just cornstarch and water, but something about that combination was magical — squishy and firm, but dripping and oozing a second later.

I paused for a second. “Maybe later.”

I was hurrying to clean up the kitchen in between phone calls, since a snow day for the kids doesn’t mean I get snow day from my work. I was flustered and already thinking through my next task for as soon as I could escape back down to my home office.

I changed my mind almost immediately.

“You know what? Yes,” I decided. “Yes, we can make magic mud.”

The kids cheered and I felt what I call “the glow of good parenting” — that momentary little high when you know you’ve made the right call, even if it wasn’t your first choice.

While I rounded up the ingredients, we launched into a big discussion of why they call it “oobleck” and I call it “magic mud.” They claimed that’s what everyone calls it on YouTube.

I Googled it and found out there’s an old Dr. Seuss book called Bartholomew and the Oobleck that’s about a sticky green substance called “oobleck.” It seems “oobleck” is the preferred name for this stuff in the U.S. and “magic mud” might be the more Canadian term.

The internet also taught me that magic mud is an example of a non-Newtonian fluid — a fluid that doesn’t follow Newton’s law of viscosity — because it changes under force to be more liquid or more solid. Science! On a snow day!

We started with two large mixing bowls, each filled with two cups of cornstarch and a few drops of food colouring. I added one cup of cold water to each bowl and the kids mixed it in with a fork, but we had to add another half-cup or so in order to get the right consistency. Then the kids alternated adding more cornstarch and more water until I had lost complete track — and we had run completely out of cornstarch.

If you add too much water, we learned, it loses the firmness that really makes it cool. Our seven-year-old daughter went a bit wild adding in water — and the cornstarch was long gone — so I tried adding a cup of flour into her mixture. It turned into a thick, flexible slime! Not magic mud, but still fun.

I took turns dipping my hands into their bowls and checking out the consistency. It was still as fun as it was when I was a kid. I also took neat slow-motion videos of them pulling it out of their bowls.

It was all very nice, but I wasn’t prepared for what my kids kept repeating as we played with it.

“Thank you so much for letting us make this!” they kept saying happily. “You’re the best mom ever!”

Each time they said it, I felt a little pang of guilt.

I didn’t feel like the best mom ever. I felt like a mom who had initially thought “No way” because she didn’t feel like dealing with the mess. A mom who was frustrated by an unexpected snow day and just wishing she could get back to work.

Less than half an hour after we started mixing up the magic mud, the kids took off to wash their hands. I cleaned up the bowls and measuring cups, and gave the table a quick wipe-down. It hadn’t been nearly as messy as I’d thought. It had been quick, too. Then the neighbours came to the door, asking the kids to play outside with them, and suddenly the house was quiet again.

I was glad I hadn’t followed my first instinct to say “No” and hurry back to my office. I was glad I’d rounded up the big bowls and used all of the cornstarch I had in the cupboards.

Twenty minutes of making magic mud and playing with it together was exactly what I’d needed.