Enthusiastic math teacher Jeff Tobes is leading one of his rigorous (but fun) walks in San Francisco June 1.

The 25-mile trek is sponsored by the Sonoma County Historical Society. Kids and adults are welcome, but Tobes said no cry babies or whiners, please.

For more information, go to www.sonomacountyhistory.org or call Tobes at 888-1670 or email him at jefftobes@hotmail.com