The Saint Louis Zoo.

The Saint Louis Science Center. Also located in Forest Park, the Science Center has dinosaur exhibits and lots of hands-on science lessons. We like the indoor bridge that spans the highway, where visitors can point radar guns and see how fast cars are traveling.

The Missouri History Museum. Another gem in Forest Park, the history museum offers in-depth and hands-on exhibits about St. Louis and Missouri. It’s more kid friendly than you would expect for a history museum. Families will appreciate the newer History Clubhouse, where kids can play and learn about history. Because the History Clubhouse can get crowded, families may need to pick up a free ticket with an assigned entry time.

The Saint Louis Art Museum.View art collections from around the world at the SLAM, another attraction in Forest Park.

The Muny. This outdoor amphitheatre in Forest Park seats almost 11,000 people and produces several popular, Broadway-quality musicals every summer. While most seats require a paid ticket, the last nine rows (about 1,500 seats) are free on a first-come, first-served basis.

Missouri Botanical Garden. St. Louis, Missouri City and County residents get free general admission to the garden on Wednesdays and Saturdays from 7 a.m. to noon. City and County residents also get free admission to the Children’s garden on Saturdays from 9 a.m. to noon. Show your driver’s license for proof of residency. Most major cities offer botanical garden entry for free or very inexpensively; Check out this list of botanical gardens from Sproutabl to see which ones are near you.

The Butterfly House. Managed by the Missouri Botanical Garden, visitors can walk among butterflies in a giant greenhouse. St. Louis, Missouri City and County residents get free admission only on the first Tuesday of each month from 10 a.m. to noon. Show your driver’s license for proof of residency.

The Butterfly House.

The Old Courthouse. Located across from the iconic Gateway Arch, the first two trials in the Dred Scott case in 1847 took place here.

St. Louis Union Station. This was once the largest and busiest passenger train station in the world. Today, Union Station features a hotel, shops, restaurants, and outdoor space.

Cathedral Basilica. Attend mass at the seat of the Archdiocese of St. Louis, famous for its architecture and mosaic artwork.

Contemporary Art Museum. View modern art exhibits at the CAM.

Citygarden. Enjoy viewing sculptures and splashing in water features at this downtown park.

Anheuser Busch. Tour the historic brewery.

Pulitzer Foundation for the Arts. Take a tour and admire art.

Saint Louis University Museum of Art. Located in a historic building, this museum features a collection of Dale Chihuly glass.

The Magic House (free only on the third Friday evening of each month). This children’s museum features hands-on science exhibits and a great imaginative play area that looks like a real, child-sized town. Be warned: it tends to get crowded.

Playing in the child-sized town in The Magic House.

Grant’s Farm. Parking is $12 per car, but admission is free to the farm, which is part zoo, part tribute to Anheuser Busch and its famous Clydesdale horses. Adults can enjoy free beer samples.

Powder Valley Conservation Nature Center. Managed by the Missouri Department of Conservation, this two-story nature center features wildlife viewing, a large aquarium, a tree house area for kids, and snake exhibits. There are three trails to hike outside.

Purina Farms. Take in a live dog show and enjoy wagon rides, cow-milking demonstrations, an animal petting area, and a barn and hayloft play area. Call ahead to make a free reservation for your family.

World Bird Sanctuary. View eagles, hawks, owls, and more. My kids like feeding chickens here and enjoy seeing the armadillo run around its enclosure in the gift shop. Bring a picnic, as there are plenty of tables to eat at. A short drive down the road takes you to Lone Elk Park, part of the St. Louis County Parks system, where you can view roaming bison and elk.

The World Bird Sanctuary.

Simple Positive Play. This new nonprofit provides an indoor play area in North St. Louis County with toys, books, and art supplies. Location and times may be subject to change, so check their Facebook page.

August A. Busch Memorial Conservation Area. Located just outside St. Louis County in neighboring St. Charles County, this area features a visitor center with aquarium and exhibits, as well as hiking trails.

Columbia Bottom Conservation Area. Managed by the Missouri Department of Conservation, this area features a visitor center with kid-friendly exhibits and an indoor bird-and-wildlife-watching area. A short trail leads to an observation area where you can view the point where the Missouri and Mississippi rivers meet.

National Great Rivers Museum. Learn about the Mississippi River’s ecosystem and tour the Melvin Price Locks and Dam.

Audubon Center at Riverlands. Built among restored prairie marsh and forest, not far from the National Great Rivers Museum, this is the place to learn to identify birds and use spotting scopes to view them outdoors. Our family happened to visit on a weekend when a live eagle was on display, trumpeter swans were migrating overhead by the hundreds, and Audubon bird experts were on hand to answer questions. It’s a short drive to the Edward “Ted” and Pat Jones Confluence Point State Park, where visitors can hike along the Missouri River to see the point where it joins the Mississippi River.

Cahokia Mounds. Located over the Mississippi River in Illinois, view the remains of the most sophisticated prehistoric civilization north of Mexico. Cahokia was larger than London was in AD 1250. Admission is free but donations are appreciated.

Lewis and Clark State Historic Site. Also in Illinois, learn more here about the adventures of America’s famous explorers.

Willoughby Farm.Visit this farm in Illinois with antique tractors, animals, and trails.