Have one free day in Houston? Here are things to do in Houston, with kids, to make for one big gigantic day of fun!

My kids and I recently planned one jam packed, big, gigantic, perfect day in Houston. We fit all of this fun into one day, but if you are more sane than the BigKidSmallCity crew, feel free to drop an item or two.

For us, a perfect day usually includes visiting the Museum District and Downtown. Lucky for us, this means parking once and riding our favorite METRORail.

We always have good intentions for starting early, but 10:00am seems to be the magic time for us getting out the door. We drive over to Natachee's and park in the lot just north (across Berry) of the restaurant. Here there is free parking for Natachee's but since we're heading out for the day, we put our $3 in the slot.

You may know that the BigKidSmallCity crew likes to eat, and with this being the case, we head to Natachee's for an early lunch. Natachee's has a patio, with a sandbox, right next to the METRORail tracks. What could be better than eating, playing and watching the trains go by?

After our lunch we go right outside the restaurant to the METRORail station. Here we buy $1.25 tickets from the machine. Cash and credit cards are accepted. (Kids under 5 are free.) When the northbound train arrives, we jump on.

In a couple of minutes we arrive at the Main Street Square Station. Here we jump off the train, Purell 6 little hands and waive at the driver. Sometimes we even get the train whistle blown for us.

Downtown is one of our favorite Houston destinations. There is the JP Morgan Chase Observation Deck, 60 floors in the air, there are the miles of tunnels underground, there are restaurants, trains and parks. For a list of things to do Downtown, go HERE. We've decided to go to Discovery Green, just 5 blocks east(ish) of the Main Street Square Station.

I have Brooke in the small stroller with our diaper bag, spare clothes and water in the bottom pocket. James is still in the BABYBJÖRN
and Joe walks next to me. We look like a small parade making our way through the city streets.

At Discovery Green, the kids play on the playground and then cool off at the splash pad. There is so much to do that we could spend all day, but instead we change clothes quickly and continue on our adventure.

On the way back to the train station, we stop at Phoenicia Specialty Foods to grab a quick snack for the road. We take our cookies and nuts and walk the 5 blocks back to the Main Street Square Station. Here we buy another one way ticket for $1.25 and jump on the southbound train.

We ride the train past our car parked next to the HCC/Ensemble station and jump out at Hermann Park. Here we walk over to the Houston Museum of Natural Science.

Inside the museum we visit the awesome new Paleontology Hall, Joe's favorite Energy Hall and Cockrell Butterfly Center. If you want to visit but are not a member, you might want to skip the general admission ticket and just visit the butterflies. The Butterfly Center ($8) is loads of fun for the kids.

Not ready to finish our adventure yet, we walk across the street to the Hermann Park Train Station. At these mini stations, no ticket is required. When the train arrives, we jump on and ride it around the park, over to Kinder Station.

Here we must decide if we will feed the ducks, rent a pedal boat ($9/boat) or visit the Houston Zoo. My kids pick the Zoo and we head inside.

Already hot, we head over to the 4D Movie Theater. Here we catch the Dora and Diego Movie and spend 10 minutes in the air conditioning and get blasted by air and splashed with water.

Feeling better, we go further into the African Forest, past the rhinos, giraffes and splash pad to the Wildlife Carousel. We buy tickets for the big kids and I ride (supervise) for free. After a quick stop at the playground in the Children's Zoo, we decide to head out of zoo.

For dinner, we stop at Pinewood Cafe, inside Hermann Park, and eat grilled cheese sandwiches. After some people watching through the floor to ceiling windows, we head out.

Instead of buying train tickets at Kinder Station ($3 each), we make the walk through Hermann Park. We feed the ducks with our grilled cheese crusts and then go to the Hermann Park METRORail Station.

We buy more one way tickets ($1.25 each) and jump on the next northbound train. At the HCC/Ensemble Station, we hop off and cross the street to our car.

On the way home we talk about our adventure until 3 kids doze off. What a great big gigantic day!