As anyone in their 50s or 60s can tell you, there’s still a lot of learning, exploring, growing—and, yes, mistake-making—to come.

Midlife is just another milepost, not a stop sign.

Her teaching methods paid off at home too: Her three daughters are YouTube CEO Susan Wojcicki, 23andME CEO Anne Wojcicki, and anthropologist and professor Janet Wojcicki.

We asked Esther Wojcicki, 74, author of How to Raise Successful People: Simple Lessons for Radical Results, award-winning high school journalism and English teacher and influential leader in education reform and founder of the Palo Alto High Media Arts Center, what wisdom she’d impart to her 50- or 60-year-old self.

Given how her life turned out, what does she wish she’d known two or three decades earlier?

Still a force in the classroom, Wojcicki has gained national attention for her innovative collaborative and hands-on approach to education.

Her teaching methods paid off at home too: Her three daughters are YouTube CEO Susan Wojcicki, 23andME CEO Anne Wojcicki, and anthropologist and professor Janet Wojcicki.

Retirement is overrated

“I think retirement is overrated,” says Wojcicki. “When I was 50, everybody else was already planning to retire, and a lot of people did. I saw what happened to people in the previous generation who retired, and I didn’t want to be like that. That’s why I’m still working full time, teaching high school, and doing teacher training.

“You see people in their 60s and 70s become lonely because they’re sitting there alone, doing nothing. It’s fun to be involved in the world. There are so many things you can do to help—you can volunteer, you can do something else for work. If you’re healthy, you have an opportunity to contribute to the world.”

This is part of a series of Interviews conducted by Max Alexander, Austin Kilham, Lynn Shattuck, and Emily E. Smith.