Plant #2

It's hard to tell in this photo, but this plant is fairly tall, currently at 17"

Plant #3

Plant #4

Plant #5

Plant #6

#1 Epipremnum (Pothos)
#3 Hedera, possibly H. helix, ivy
#4 Chlorophytum (spider plant)
#6 maybe a Plectranthus

You may want to post in the house plant forum also.

#2 looks like a Mandevilla and #5 looks like a weed.

What about Pilea for #5? P. microphylla maybe?

I don't think Mandevilla has compound leaves.

#6 looks like swedish ivy

#5 is artillery fern. Some people grow it (I've seen it in nurseries!) and some think of it as a weed.

Swedish ivy is Plectranthus.
Artillery fern is Pilea.

Did you ever decide on #2, Aircad?

Yes, over in the houseplant forum it was decided that it is a Schefflera plant.

Thanks for everyone's help!

Cool! Thanks for the update, surprised I didn't see that over there.

Maybe it's just the angle of the pic, but I don't think I've seen a Scheff like that, and wasn't sure the leaves at the bottom are part of the same plant. Neat-o.