I attended salsa classes held by the Latin Collective for ten months, and I cannot recommend any…read morebetter place in Cambridge if you really want to learn salsa starting from zero. They have classes of two hours each Friday teaching new york style salsa and occasionally bachata; classes are "drop-in" which means that you can come whenever you please according to your interest and availability; there are four-five different levels, so you don't need to worry too much about staying with people too much more experienced than you. The teachers are professional, kind, and passionate in explaining you the steps and giving some personalized advice when it's the case. The price (8 pounds) includes the access to the dancing floor until 1am after the classes; there is always a lot of people so it's relatively easy to find someone at your level to dance with. When my friends asked me to go out on Friday I always replied them: "Sorry guys, let's do it on Saturday, I have salsa tonight!".