I had tutored privately for friend's kid on his high school chemistry and math during my college life back in 2010 for 3 months in Berkeley, CA, and he successfully advanced to A in his junior year final exam.

Also I spent another 2 months back in China tutoring a high school senior during 2008 to help her English and chemistry. She improved to B from D as a result in the final exam. Though not exactly "tutoring", I helped my fiancee to prepare for her GRE and career certification test as...