In the Richard N. Merkin Center for Pure and Applied Mathematics high in Caltech Hall, the American Institute of Mathematics (AIM) gathers mathematicians to solve confounding puzzles, often using only chalk. AIM carried that analog approach outside to celebrate its 30th birthday with a free public math party on the lawn beside Caltech Hall on June 29.

Hundreds of families and individuals turned out to play math games while sitting on blankets spread out under trees and at tables under a shaded arcade. Pythagoras would have felt at home.

At more than a dozen stations, volunteers coached participants and explained the mathematical principles at work in games including SET, Prime Climb, Rubik's Cube, wooden 3D puzzles, unfair dice, and walking puzzles. Traditional paper games featured wolves and sheep, cats and dogs, and magic circles. One improvised paper game taught children to spot base systems, from binary's base 2 to the ancient Sumerian and Babylonian base 60.

"We wouldn't have been able to pull off this milestone event without the incredible dedication and enthusiasm of everyone who volunteered to help," says Sergei Gukov, the John D. MacArthur Professor of Theoretical Physics and Mathematics and consulting director of AIM. The volunteers included AIM staff, postdoctoral scholars organized by the Caltech Postdoctoral Association, Caltech professors and students, and math professors and teachers from around LA.

"Today's activities opened my eyes to non-online games, ones families used to play around the dinner table. This is where a child's exponential growth starts," said visitor Ms. Y. M. Wong. She is homeschooling her son, Atti, who played beside her, and she relies on math circles and activities like the AIM fair. "I wasn't sure how homeschooling would go, but with this kind of community, I am happy."

By way of fuel and fun, children lined up for free churros and Sno-Kones, transformed their looks with free face painting, accessorized with balloon animals, and crowded the podium during raffle announcements for free games and books to take home. A taco truck did brisk business.

AIM's birthday party drew hundreds of people who wanted to engage their curiosity, challenge their minds, and play together. That same sense of community is vital to progress in mathematics as the field transitions from an individualistic model to a collaborative one, says Gukov. The collaborative model was not widely accepted 30 years ago. Gukov credits its gradual adoption to the foresight and dedicated efforts of AIM's founders. Together with the Merkin Center (which took in AIM in 2023), AIM continually works to connect people, from the wisest mathematicians to the newest.

Written by Ann Motrunich