TRUCKEE, Calif. — During a volunteer trip to Tanzania, Truckee High School senior Hattie Kaplan was caught off guard by her period. When her mentor handed her a box of sanitary pads, she scoffed at first — the pads were bulky, diaper-like and heavily mint-scented.

Then she realized they were more than most girls could hope for.

“No, women don’t have to deal with that,” Kaplan said, referring to the uncomfortable pads. “If women are privileged enough, they get to deal with that.”

While working at a local school, Kaplan learned that many of the girls there had no access to menstrual hygiene products at all. Instead, they used rags and often stayed home from school while bleeding — missing class and falling behind through no fault of their own.

Research supports what she saw firsthand. One study in northern Tanzania found that 47% of girls left school early during their last period, while 31% participated less in class and 33% found it harder to concentrate. Another study connected poor sanitation and a lack of menstrual products with lower school enrollment and higher dropout rates among girls.

A few weeks later, back in Truckee, Kaplan stood in the pharmacy aisle, looking at shelves full of menstrual products — aware, for the first time, of the privilege that access represents.

From that experience, Kaplan decided to organize a 5K race and community festival to raise awareness and funds for menstrual health education and product access in the community where she volunteered: Moshi, Tanzania.

The event will take place Sept. 21 at Truckee Regional Park and will feature local vendors, a raffle and a bracelet giveaway with each race registration.

Kaplan has partnered with CouldYou? Cup, a nonprofit working to end period poverty through education and distribution of reusable, medical-grade silicone menstrual cups.

In addition to supporting product distribution, Kaplan plans to help fund the development of a children’s workbook focused on body literacy, self-confidence and menstrual health — resources she hopes will support girls in understanding their bodies and rights from an early age.

Over the past few months, Kaplan has reached out to local organizations, town institutions and community members for support. So far, eight vendors and eight community partners have signed on — contributing food, raffle items and services.

“I complain about paying $20 for a box of tampons,” Kaplan said. “But there are girls around the world who don’t even have access to them.”