What a wonderful find! The Santa Monica Public Library offers free story times at each of its 4 branches. There are sessions for babies, toddlers and preschoolers. Schedules for each branch are posted on smpl.org. A great activity for even the smallest child!
If you are in Santa Monica for any period of time during the week. Check out the schedule for story time at the Library. The staff is amazing and story time there is the best we've found on all our travels. They sing, play musical instruments, dance, read books, count, it's interactive and appropriate for many ages and easy to love. I've taken my Daughter for the last two years when we are in town and she loves it. The bathrooms there are even clean and kid sized, so "I can do it by myself" isn't a problem. Also at the library you can often catch a free family movie. Be sure and check the website or call ahead.