I would also recommend www.activemoms.com, you subscribe (its free) and they email you the schedule each month. Every day there are suggestions of things to do with your kids and it is all based in the valley. I also recommend the same suggestions as a lot of the moms here: AZ Museum for Youth in Mesa, just for the day and they also have classes you can enroll in, Phx Children's Museum downtown, Sea Life Aquarium- although be prepared to WAIT OUTSIDE for 45 mins the first time-we've been 3 times already (got the yearly membership)...once you have a membership you can skip the line and go right to the front. Once you are inside though, it is not crowded...people are constantly moving so it doesn't get overwhelming, book stores and libraries have storytimes all the time and occasionally puppet shows, magic shows, etc, head to a farmer's market, the zoo does night camps for kids or else like another mom said very early in the morning is cooler (or you could just head there and hang out at the 2 splash zones right in the zoo), and the biggest suggestion I could give is to utilize gilbert parks and rec dept or Chandler parks and rec...unfortunately the summer session just started this week so you might be too late, but there are awesome classes for all ages and they are very reasonably priced. If you are really savvy, sometimes you can arrange a class for your little one (mommy and me) at the same time as a class for your 3 yr old at the same location so you aren't just waiting around for the 3 yr old's class to end trying to entertain your baby. Oh, we just went to Superstition farm for a class through parks and rec, but I noticed they do tours for anyone for a fee. It was pretty fun, I have to say...my kids loved it. Splash pads and public pools are all over...Mesquite Groves is a really fun pool, and they have a toddler area with smaller slides where the footing is all rubberized. Freestone Park is fun, get some duck feed and feed the ducks or they also have a little train you can ride around the lake and a little merry go round, ferris wheel, etc but the train and other rides only run on I think Fri, Sat, Sun. Mccormick Stillman Railroad park in Scottsdale is fun, they have a train also that runs year round, there is a little ice cream shop you can get a scoop at, there's also a merry go round there, a little store to buy train related toys, etc. Oh, also the Great AZ Puppet Theater does puppet shows for preschoolers and Childsplay at the Tempe Center for the Arts also does plays for young children. There's actually lots to do if you just have the right links...have fun!