Ultra-shallow clear waters protected by a reef make Bathtub Reef Beach a perfect swimming spot for very young children. It really is calm like a bathtub, which is not the case for most of Southeast Florida's beaches. On weekends families gather on the pretty, curved beach and kids high-tail it for the water. They can splash and have a blast in the knee-high water. Close to shore there are miniscule little waves that come at angles making for some fun water play.

Bring a beach umbrella and plenty of sunscreen because there is no shade. The sun is super strong in Florida.
An abundance of large whole shells can be found on this beach and even more on Chastain Beach, just a few steps to the north.
Snorkelers can swim out a short way and observe little fish swimming around on the reef. Come at high tide when the water is crystal clear, and come when the waves are flat. 
The sand at Bathtub Reef Beach is coarse and dirt-colored. But the shells more than make up for this.
There are restrooms, showers, and a lifeguard.
Sometimes the surf is high, and the waves come over the reef, making this beach better for surfing than for wading with young children.
There is a huge gazebo high above the beach where you can sit in the shade and feel the cool breeze, if you've had enough of the sun. The dunes at this beach are high, and you can stand on the top and get a good view up and down the beach!
Sailfish Point, at the end of the road, has a cafe but it is only for members. Instead, eat at Drift Kitchen in Hutchinson Shores Resort, for gorgeous beach views and good fish tacos. It is an eleven minute drive north along Highway A1A.
For amazing views of the ocean and the intracoastal, stop at the House of Refuge on your way.

Directions

Bathtub Reef Beach is located at 1585 SE MacArthur Blvd, Stuart FL 34996, the last beach on the southern tip of Hutchinson Island.
From Highway 95, exit at Kanner Hwy and follow it for six miles to the northeast into Stuart. Turn right on NE Ocean Blvd and head over the causeway to Hutchinson Island, for five miles. Turn right on SE MacArthur Blvd and follow it for a mile past a golf course and then several beach parking lots. Pull into the Bathtub Reef Beach parking lot on your left.

Click on map for interactive view