Things to Do in Nashville (or Middle TN) with Kids

I've searched over and over for free (or almost) free things to do with all the kids this summer. We've started making out "bucket" list, and I'm sure we won't get to half of them, but here's some of our list of possibilities.
1. Visit the zoo. We purchased a membership to Boonshoft Museum to use this summer at area places including the zoo. It's $5.00 to park, and we'll take a sack lunch to enjoy at the picnic tables.
2. Visit the Science Center. Science in Toys opens June 16th.
3. Go to the Discovery Center.
4. Splash at the Splash Pad and have a picnic supper with Dad.
5. Paint some pottery ($3.00 per painter on certain days, plus the pottery--my kids have a $5.00 a piece limit when we go)
6. Go bowling!! Kids bowl for free at several area bowling centers. All we'll pay is shoe rental!
7. Visit the Farmer's Market (or several) in our area.
8. Play in the sprinklers in our yard
9. feed the ducks at Centennial Park. See the Parthenon from the outside (they love the Percy Jackson movie)
10. Go to the cheap summer movies here and here.
11. Go to VBS at our church. The kids LOVE this (and it's FREE).
12. Go to Beechbend Park or Nashville Shores. so it's not free, but it's a fun special treat get-away close to home.
13. Ride the Go Carts and play Putt-putt here.
14. Go to the library for story time and to read.
15. Make stuff!
16. Learn about something new--a place we want to visit, an animal, a foreign country, a new food.
17. Watch a movie at home when it's too hot or too rainy to get outside.
18. splash in the puddles around our house during a rain shower.
19. Visit dad at work and have lunch
20. have a yard sale.