Male Emerald Damselfly (Lestes sponsa)
Female Emerald Damselfly
Pair of Emerald Damselflies
Pair of Darters (probably Black Darters - Sympetrum danae)
Watch a video of two pairs of Darters laying eggs.
I also found this empty larva case (exuvia) of a Common Hawker (Aeshna juncea) - one of the larger dragonflies.