Youth & Family

Thingamajig Invention Convention

Ages 5-14 San Francisco County Fair Building
Sparking Curiosity, Showcasing Youth’s Creativity
Children gather around a science project at an event, observing a contraption with a plastic bottle and white bowl. An adult supervises, and many attendees wear green shirts.

Thingamajig® is a Science Fair & Engineering Expo

Thingamajig® offers more than a dozen hands-on challenges designed to spark curiosity and showcase kids’ S.T.E.A.M. skills while they have fun building or simply designing new inventions. It is in its 29th year nationally, and 9th year at the YMCA of San Francisco. It’s one part science demos and activities and another part engineering competition.

THINGAMAJIG 2018 Invention Convention - San Francisco" on a black background.

Inspire Youth to Be Amazing and Unstoppable!

Join us! The world needs more innovators and hands-on problem-solvers.

WHEN: Friday, June 27, 2025, from 9:45 AM to 2:15 PM

WHO: All K-8th Students enrolled in the YMCA of San Francisco’s Summer Programs

WHERE: The San Francisco County Fair Building, 1199 9th Avenue, San Francisco, CA 94122. Located next to the San Francisco Botanical Garden in Golden Gate Park.

A smiling boy in an orange shirt and camo jacket holds a colorful craft project. He is indoors with other people in the background.

Is your organization interested in group volunteering?

Contact Jennifer Trombley at [email protected].

Upcoming Events

Mar 24

After School

J Ortega – School Year 2024-25 – After School 2 Days

Kids (Ages 0-17), Kids (Ages 4-12)
Stonestown Family YMCA
March 24 at
12:00 am – 11:59 pm
Every Monday, Tuesday, Wednesday, Thursday, Friday from August 19, 2024 to June 4, 2025
$50 non-refundable / deposit + monthly payments that occur on the 1st of month (or 1st business day after) from August 2024 through May 2025 – Non-Member $269 per month – Member $215 per month

Mar 24

After School

Jose Ortega Elementary School – School Year 2024-25 – After School 5 Days

Kids (Ages 4-12)
Stonestown Family YMCA
March 24 at
12:00 am – 11:59 pm
Every Monday, Tuesday, Wednesday, Thursday, Friday from August 19, 2024 to June 3, 2025
$50 non-refundable / deposit + monthly payments that occur on the 1st of month (or 1st business day after) from August 2024 through May 2025 – Non-Member $630 per month – Member $504 per month

Mar 24

After School

Jose Ortega Elementary School – School Year 2024-25 – After School 3 Days

Kids (Ages 4-12)
Stonestown Family YMCA
March 24 at
12:00 am – 11:59 pm
Every Monday, Tuesday, Wednesday, Thursday, Friday from August 19, 2024 to June 3, 2025
$50 non-refundable / deposit + monthly payments that occur on the 1st of month (or 1st business day after) from August 2024 through May 2025 – Non-Member $390 per month – Member $312 per month

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