Green frogs aren't necessarily green. They come in green, brown, and occasionally blue. They also get nearly as large as bullfrogs, large enough to eat small mice and birds. They also have the ugliest call. It sounds like a bad out of tune banjo *GLUNK!*
Dawn, green frogs and bullfrogs lay eggs in late summer. Sometimes their tadpoles overwinter as larvae (and get BIG!). I can't suggest anything. Maybe transplant them to the closest water (where the other frogs would be going). But do NOT put them where there aren't any green frogs. The adults are voracious!