San Diego public transportation runs by bus and by trolley. When you arrive in San Diego, go to the i transit store located downtown at 102 Broadway St. Buy a month pass ($68) for public transportation and you can ride all San Diego busses and trolleys for a month. It's very convenient. If you are here for two weeks or less, you can buy a half month pass ($34) or a day pass ($5). There are lots of options. Ask the person at the counter and they will help you.
How to ask for advice:
Excuse me, can you help me? I am in San Diego for X weeks, what kind of pass should I buy?
Directions from the school:
Walk down Fifth Avenue and turn right on Broadway St. The store is at the corner of Broadway and First Ave. It's open Monday-Friday from 9 to 5.