We've spent a lot of time at Coyote Point Museum. We used to do the Toddler Tuesday programs - I'm not sure if they still run those. My daughter also did half-day camps there (and both kids went on field trips to Coyote Point).
review of Magic Mountain playground on Trekaroo.
You could easily spend the day or at least half a day there. Bring a lunch! Coyote Point is in San Mateo, close to Burlingame and not too far south of the airport. There is sometimes a $5 car admission fee, if the attendant happens to be at the booth (fee is waived for museum members).
Today and tomorrow, the Savvy Source is offering a deal for 4 tickets (2 adult, 2 kids) for only $10 (half-off). I think you have to use the entire coupon at once (you can't split it into two days with 1 adult/1 kid each time).
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