Beaches here in central FL tend to be really short due to beach erosion and the walk through the grass is covered in sand spurs. The sand at most beaches has a lot of iron in it -- drag a magnet across it and you can collect stuff that looks similar to the iron filings in kids toys. You can still find some white sand quartz beaches around and the sand "barks" when you kick it hard enough. Shuffling your feet through it on a really dark, moonless night will also create sparkles based on the piezo effect.
The bad beaches? Lots of those, too. I have no idea why, but there are still public beaches along the Northern part of Tampa Bay and people still pull off the causeway to let their kids splash around and build sandastles out of the somewhat slimy, dark-grey sand. I think if people knew what the first three feet of the bottom of the bay was made up of, they wouldn't be walking around or swimming in that water.
Other fun aspect of beaches down here: red tide. All the fertilizer and warm summer waters makes a bad mix at least three times a year and when it hits and the wind blows inland, the toxic smell will burn your lungs. Spicy!