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Mary Tollefson was a teenager when the United States entered World War II and she was determined to be part of the war effort — not just by keeping things running on the home front.

Her mother said no.

So Mary went to work for the phone company, where she signed up for a new electronics course. She had only attended three sessions when she finally got to join the service — but those sessions were enough for her to be hooked. Mary became an electrician with the WAC, as well as a driver and mechanic.

That’s how she came to use her first computer. It was at the ballistics lab where she was part of a team calculating trajectories, and it was the size of a large room.

“That kind of experience you only have once in a lifetime,” Mary says in the video “Mary: The Wisconsin WAC.” Service gave me so many chances to do things I never would have done.”

Watch an exuberant Mary describe her experiences in this fascinating video, which was made not long before the former servicewoman passed away on October 24, 2015, at age 93.

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