It’s Engineers Week, and today is Introduce a Girl to Engineering Day! As a college student, I was an active member of my university’s chapter of Society of Women Engineers (SWE). Volunteering to do outreach to school aged girls was my absolute favorite part about being in SWE. I loved showing young girls how cool and fun engineering can be, and spark their interest in math and science.

Now that I have a daughter, I love sharing my passion for STEM with her. She knows that both my husband and I are engineers, and she regularly tells me she wants to be an engineer when she grows up.

She often digs through recycled materials I have saved in our craft cabinet and uses them to build. Then she’ll call me over to come see her creation and proudly tell me, “I was an engineer today Mama.”

To celebrate Introduce a Girl to Engineering Day I wanted to do a special engineering activity with my 4 year old daughter. We dug around in our craft cabinet today and found that we had no fewer than 10 toilet paper rolls saved! It was a sign we had to do something with the toilet paper rolls.

Bowling with toilet paper rolls

Last year (pre-covid) I took my kids bowling for the first time. They’ve been talking about it ever since. Since we happened to have ten toilet paper rolls we decided to use them as bowling pins.

1. We started by decorating all the toilet paper rolls. Just because we’re engineering with them doesn’t mean they can’t be pretty! And I’m a firm believer in STEAM for kids, which means fully incorporating Arts into all STEM activities. I want my kids to explore their creative side while building their analytical thinking.

2. Next, I taught my daughter how to set the toilet paper rolls up like bowling pins in a pyramid formation. She counted as we placed four pins for the back row, three pins for the second row, two pins for the third row, and one pin in the front.

3. We discussed what size ball would work best to knock down the rolls: a small, medium, or large ball. She firmly believed her large ball would work best, and I agreed. We discussed because it had more surface area it was more likely to hit and knock down more pins at once.

4. Finally, we talked about where to aim the balls. I explained that she should aim for the center pin because as it falls it will knock down the other pins behind it. Discussing where to aim, and actually executing it are two totally different things, especially for young kids that are still developing their hand-eye coordination skills.

Sometimes she threw just right and hit the pins on her first try, and sometimes she didn’t. But we discussed how with each throw she is learning and adjusting and making changes to do better the next time.

Building with toilet paper rolls

When we were done bowling we decided to try to build with the ten toilet paper rolls. We tried it two ways: stacking the rolls horizontally and stacking them vertically. Which way do you think she had more success?

1. We discussed stacking the rolls in the same pyramid pattern that we used to set up the rolls like bowling pins: four rolls for the bottom layer, three rolls for the second layer, two rolls for the third layer and one roll on top.

2. When we stacked the toilet paper rolls horizontally, my daughter couldn’t stack more than two layers before the rolls started rolling away from each other and the tower falling down. Eventually, I helped her by holding the bottom layer in place so she could stack the upper layers. We talked about how the rolls are round and they roll and so can’t form a strong base to support the tower without our hands or other props as support to keep them from rolling.

3. We had much more success stacking the rolls vertically. This tower was challenging for her because the rolls are thin and some were bent, so she had to gently place the upper layers just right, but she did it on her own after just a few tries!

Simple everyday play like this is the perfect way to introduce young kids to engineering. Today my daughter learned to analyze problems and think of solutions when we discussed ball size and how to set up the toilet paper rolls as bowling pins. She learned about trial and error when she didn’t knock down all the pins on her first try. She learned there are more than one way to look at a problem (should we stack the rolls horizontally or vertically?), and there may be more than one right answer. She learned that building isn’t always easy: it requires attention, focus, and precision in the placement of the rolls.

I hope our simple playtime learnings inspired you to start saving your toilet paper rolls and encourage your curious girl (or boy!) to start engineering at home!