Need help saving large amounts of frogs in my pool!?

I'm from Connecticut and there are at least 100 or so small green frogs in my pool and tons of tadpoles. We've put floats and things in there for them to crawl onto but last night all the tadpoles and underdeveloped frog-lets suddenly died and we've no clue why but the frogs are all still alive and we want to save them. The closest pond is down the street but I've no idea how to catch them all and transfer them...I want to save as many as possible but I don't know what kind of frogs they are, what they need or how to do it and seeing the dead ones is heartbreaking after having watched them grow for the past few weeks. Any suggestions would be appreciated?