We will be based in Sorrento for a week the first week in July. Can you recommend any sandy beaches that also offer some sight-seeing but are not too crowded? The girls and I will love relaxing on the beach for awhile but my husband and son like to explore and do water sports. We are planning on spending a day in Capri. I haven't planned any other island excursions yet.
If by sandy beaches you mean cliffs and rocks there are a few beaches near Sorrento.
http://www.sorrentodreaming.com/what-to-see/beaches-of-sorrento/
We love taking day trips to different islands so the beach does not need to be in and around Sorrento.
The only true sand beach I've seen on the Amalfi Coast is in Maiori.
You'd need to take 1 bus from Sorrento-Amalfi, then change to a bus from Amalfi-Maiori. Or 2 seperate ferries again changing in Amalfi to reach it.
Edit: if memory serves me correctly, someone on the beach rents Canoes and paddle boats.
Check out Meta. Gray sand beach, mostly locals.