There are innumerable tours through Chinatown, but if you want an insider's look at the rich and little-known stories of one of the country's most densely populated neighborhoods, join up with a tour led by San Francisco high-schoolers who are part of the Chinatown Community Development Center's after-school program. The tour's eight docents -- all of whom have lived in Chinatown -- spent the summer of 2000 researching and gathering oral histories; in the past year, they have transformed these stories and facts into an intriguing glimpse of their neighborhood. The $8 tour takes you through side streets and alleys you never knew existed, highlighting spots like Dr. Sun Yat-sen's secret campaign headquarters from the early 1900s; the first segregated public school for "Oriental" kids, which opened in the late 1800s; or the tiny barbershop run by Mr. Yee that still caters to visitors such as Matt Dillon and Michael Douglas.