About

Math educator, mama, and founder of The Number Nook.

The Number Nook was founded by Sadie Wilhelm to help children build strong math foundations early, grow their confidence, and give families a clearer picture of progress over time.

The Back Story

After graduating from Stanford, Sadie started her career as a math educator, initially as a high school math teacher and then as the founder of a math tutoring business in San Francisco. In the midst of selling her business, she learned to program computers and found herself in the tech world, first in analytics and then in software engineering, ultimately managing engineering teams at Pinterest. While she enjoyed the technical challenges of her job, she yearned for the human connection and sense of impact she had experienced as an educator.

After taking some time off, Sadie began to volunteer in her daughter's classroom and invest time thinking about creative ways to teach her number sense. During that time, she often found herself reflecting upon her time working with older students: a child who had strong foundations but was stumbling with a new concept was always easy to get back on track, but for a student who still struggled with basic integer operations, the path was much longer and more difficult. Moreover, that student's confidence in herself had long been lost, and this was perhaps the hardest battle to fight.

Through this journey, Sadie realized that she had a unique opportunity to nurture a fondness for and aptitude in math amongst the kids in the community, starting early. With this goal in mind, she launched a series of math enrichment classes. As she helped more families, she expanded her service offerings to include assessments, at-home education plans, and parent advisory.

Our Team

Meet the people behind The Number Nook.

Founder

Sadie

Sadie has a long history as a math educator in the Bay Area. After graduating from Stanford, she was a high school math teacher and then founded a math tutoring business in San Francisco. Eventually, she sold her business and spent a decade in the engineering world. Now, as a mom, she has found herself back to her educator roots, working with kids and parents to make math fun and approachable.

Math Instructor

Alex

Alex is a Mill Valley native who returned home after graduating from UCSB in 2024. Since then, he has been working 1:1 with elementary, middle, and high school students to help them succeed in math. He is passionate about teaching and making learning fun for kids of all ages. In his free time, Alex enjoys playing soccer, videography, and farming olives at his grandparent’s ranch.