Smash Gyms, Mountain View

Smash Gyms' list of instructors reads like a classified roster for some kind of elite instructor squad. The kickboxing instructor, Sam "The Ram" Spengler beats people insensate as a professional MMA fighter when he's not teaching junior-high students. Michael Jen, a third-degree black belt, engineered his own method of teaching Brazilian jujitsu after practicing the graceful art for 20 years.

What they share is a love of teaching. Jen draws on his wealth of experience studying under renowned teachers such as Roy Harris and Joe Moreira to impart his wisdom and high kicks to students. "The Ram" leads upbeat, fun kickboxing classes to help pupils reach their fitness goals, such as losing weight or being able to roundhouse kick the tempting ice cream offered to them.