Center School third graders learned about electromagnetism as Brendan Cole from the Museum of Science Boston Traveling Program showed them what positive and negative charges can do.

Cole, with the help of lab assistants, AKA the kids in the audience, demonstrated how invisible forces are at work everywhere.

Although “we're mostly made of the same number of positive and negative charges,” Cole explained, there is a way to unbalance that.

Mackenzie Crowley stepped up as the guinea pig.

“Do you mind of I separate your charges?” asked Cole, who proceeded to rub the third grader's head with a balloon.

The resulting static electricity stood her hair on end.

Using a Van de Graff generator, Cole next invited Maya Warren up to the front. As it charged, Warren touched the large metal globe, which gave the same effect as the balloon.

Cole took the kids through several other experiences that demonstrated how electrical currents are conducted, including how an electric current can catch fire.

Throughout the program, Cole stressed the importance of testing ideas as a foundation of science.

“It's great to admit you don't know something,” he said.

The program was sponsored by the Parent Teacher Association.