Recently the Marine Discovery Center, located in New Smyrna Beach, held an open house. They did this because they moved to a new location. Me and my family went to the open house and had a great time. There were exhibits, activities, and the kid's had an opportunity to learn things.
Be sure to check their calendar for events, as they offer many good ones (e.g., educational programs, homeschool programs, camps, adult programs, etc.). I've taken my kids to the Sea Squirts program, have taken eco-boat tours, and more. You can find out more about the Marine Discovery Center, including information on their new location, here.
Here's some pictures from the 2012 open house event: