One of my favorite water parks in the Bay Area. The slides are decent enough, but it has an amazing lazy river. There is a lot to be said about dropping $30 a head to let an endless loop of water carry you around on an inflatable doughnut. When I go to Waterworld I think I spend about 60% of my time floating on the lazy river.

A great water park in the heart of the South Bay. It’s not super new, or super well stocked, but you can go and ride some great water slides and get yourself way wet. They have some great slides, including one called “Shotgun Falls” which drops you significantly above the landing pool so you fall into the water.

While it’s not the flashiest mall in San Francisco, it has everything you need while still having a large free parking lot. It’s close to SFSU, so there will be a grip of college students milling about, but when don’t you see that at a mall? All that you need to know is that it’s large enough for you to kill an hour or two, and it’s well air conditioned.

Another great place to stay cool and get out of the sun, the Computer History Museum is quite a bit off the beaten path so you don’t have to worry about it being too crowded, and you most likely have never been there, so you’ll learn something. They have examples of early computers, as well as newer things. Because so much computer history has occurred in Silicone Valley, they have all kinds of remarkable artifacts of one of the most life changing technologies ever created. It’s especially worth visiting for all you Mac fans out there, because both Jobs and The Woz have donated some of their very first projects. It’s like coming home to the mothership.

My favorite lazy summer day activity is to take my iPod down to the local Borders and read a big stack of Graphic Novels. The guys at my local comic book store hated it when I did this, but oh well. It’s a nice way to stay cool, read some good comic books and save money all at the same time. It can’t miss.

I know this seems like an odd choice, but you can’t beat Ikea for a temperature cool place to hang out. If you’ve never been, it’s like Disneyland for home decoration. They set up all kinds of fake living spaces in little dioramas. You can spend hours wandering around the showroom alone. But wait! There’s more! You can duck downstairs for dirt cheap housewares. Be careful! All those $5-$10 deals add up super quick. Also, make sure you check out the snack bar. The upstairs restaurant has the best Swedish Meatballs on the planet, where as the lower snack bar has hot dogs cheaper than you can get at the Costco snack bar. VALUE!

You may be wondering why the beach is filed under “go someplace cool” instead of “get wet.” If you are wondering such a thing, I know you aren’t from Northern California. The Earth would need to move closer to the sun before I even considered sticking more than a toe into the frigid churl we laughingly call “the ocean.” Ever Bay Area child is repeatedly warned about how dangerous the ocean is. You can’t swim in it, you can’t turn your back on it, you can’t taunt it. It will kill you when you least expect it and then a shark will eat your body.

That being said, it’s always a lot colder near the beach than it is further inland. Even in the dead of summer you can expect to wear a sweater. It can get pretty windy, so be ready to bail and return to the sweet warmth of home.