Dutch Springs (PA)
Dutch Springs is one of the top scuba sites in the US. Its a fresh water lake that's used by tons of divers and shops for training and practice. They offer camping on the grounds and even have an Aqua Park and Sky Challenge for non-divers.
This is NOT a scuba site suitable for most. An extremely muddy bottom destroys the visibility as soon as you get in the water. There's not much to see or do. The only reason why I'm even mentioning this site is because of the Legend of The Lady of The Lake and its also used for ICE DIVING training in the winter months when its frozen over.
Mt Sinai Jetti
A great little scuba dive for beginner an up. Just be careful timing the tide and don't cross the waterway unless its SLACK tide. The water really flows fast and can sweep you out in the open ocean in no time at all.
The HMS Culloden
A little difficult to find, The HMS Culloden is one of the oldest shipwrecks around. She site in only about 20 feet of water and has been there since 1781. She is also a historical site so the wreck is protected. Take nothing but pictures and leave nothing but bubbles.
Beach 8th Street
Beach 8th street has some tricky parking but is still often used for student checkout dives. There's rumor of an old war mine down there (but I've never found it)
An excellent scuba site for a new diver. It is not tide dependent and offers a max depth of approx. 20 feet at most.... there is also a sunken submarine. Can you find it?
Jones Beach Jetti
Advanced Open Water Certification is suggested for this scuba site as the surge and tidal flow can really take you for a ride if you don't know what to expect. This is a site that I would suggest a guide for the first dive or two here.
Manhattan Beach Reef
I personally haven't been to this site yet so if you interested in diving here, we can go together.
Old Ponquogue Bridge is suitable for a beginner as a guided scuba dive due to the slack tide needed for optimal diving.