Follonica

Not in Follonica but in the area--there is a wealth of things to do!
Cala Violina beach
The archaeological site of Populonia and Baratti
Massa Marittima
Maremma Park
various hill towns, depending on how much driving you wish to do

Any restaurant suggestions!? Trying to find some things that are hidden gems.
Thanks!

We ate quite well in Massa Marittima, depending on how far you wish to drive, but I would get a Slow Food guide and seek out places closer to where you will be--I am sure there are some amazing seafood places all up and down the coast. We don't like to drive after dinner so we rarely get to those sort of out of town places. I'd look near Castiglione della Pescaia as well.
Resources:
guide to the region:
https://www.amazon.com/gp/product/8864334629/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
this book has a scenic drive north of Follonica that has restaurant recs:
https://www.amazon.com/gp/product/1892145685/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
food writer who lived in the area:
http://www.emikodavies.com/blog/the-perfect-tuscan-coast-getaway-2017/
general food and restaurant guide:
https://www.amazon.com/gp/product/190686831X/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
The Slow Food guide is now available as an app, but here is an older version of the book:
https://www.amazon.com/Osterie-Locande-dItalia-Traditional-Places/dp/8884991145/ref=sr_1_1?ie=UTF8&qid=1498846654&sr=8-1&keywords=osterie+and+locanda