Ishika Kumar saved the most important lesson for last during her visit to a Grade 3 class at Cootes Paradise Elementary School, just a few bus stops from McMaster.

Kumar is a volunteer with Let’s Talk Science, an award-winning, national charity that’s delivered no-cost STEM programs for 30 years to kids, youth and educators. McMaster’s chapter is among the oldest and largest, with just over 100 students from Science, Engineering and Health Sciences.

In 2022-23, the Mac crew ran 154 activities at schools and community events for over 8,200 children and youth.

The program also has some freshly minted grads like Kumar, who graduated last spring with an honours degree in Life Sciences and a minor in Psychology, Neuroscience and Behavior. She hopes to start graduate school at McMaster this fall.

For this visit with Mac students Jenny Doan and Melanie Warnakula, Kumar mixed a physics lesson with hands-on fun. Four teams of students put on their science and engineering hats and had 30 minutes to build a tower out of spaghetti sticks, string, tape and a marshmallow.

When time ran out, Kumar measured the height of the towers and checked to if she could blow the pasta towers over with a fan. Team four had run into trouble with their tower and Kumar rallied the class to help out.

This is when Kumar delivered her most important lesson. “The first time you do an experiment doesn’t mean it’s going to be the best time. You might have to do it a thousand times before it’s the best.”

Every scientist knows all about trial and error, said Kumar. If at first you don’t succeed, scientists try and try again and ask others to pitch in. She pointed out that every team had come up with a unique idea. What if they combined those ideas the next time to build an even taller and sturdier tower?

The kids also asked a ton of questions before, during and after the experiment. Why does the Leaning Tower of Pisa lean and why hasn’t it fallen over? Is McMaster making the computer implants that go right into people’s brains? Are you a PhD student? Did you know that crash test dummies aren’t actually dumb? Did you know the Earth spins around the Sun and not the other way around?

“Can I eat the marshmallow?” was asked more than once and kept getting a hard no from the teacher. Kids who wanted to hold onto their pieces of string got the green light.

The visit wrapped up just as cookie club was announced over the PA system. The kids made a beeline for the door but not before thanking Kumar, Doan and Warnakula for the science lesson. And checking one last time if they could eat the marshmallows.