Summer Fun for the Buddy

I'm sure you know already, but it is May.  Summer is almost here.  I'm trying to find a few things for us to do this summer that the buddy will enjoy.  He is almost 1 1/2.  Greg and I work during the day. We need some good weekend options.  Below are some of the things we are already doing this summer, but could use a few more.

Baseball Games
We are actually going to a minor league game this weekend and it just so happens to be Star Wars weekend at the ballpark.  Greg and I love baseball, so I'm sure we will go to a few games this summer.

NC Zoo
We are going to the zoo in July.  Carson loves animals.  We would love to take him to the aquarium but both the zoo and aquarium are a few hours away.  What is the best way for him to see some other animals?  I don't mean the pig or guinea that roam on our property.  

We have a little pool that we can put outside and we plan to do some baby swim lessons through our gym.  Would he enjoy splash pads at this age?  

What are some other ideas for a very active little boy to do this summer?