I think your grass is Deertongue. Here is a link that might be useful: Dichanthelium clandestinum

Well... of course, as soon as I post this I find a list from the Arbor Day order (or at least, I think it was that year's order). No idea which is which (which of the ones that came in this bundle actually survived), but could the third photo be a young Sargeant Crabapple? That's on the list, as is Eastern Redbud, Washington Hawthorn, dogwood (I know it's not that), Goldenraintree and crapemyrtle (I remember wondering why on earth they were shipping crapemyrtles to New England!!) In theory (meaning assuming they sent what they said they were sending), it should be one of those -- and the crabapple seems like the only one it could be? I'd be floored if they were shipping free Bradford pears (which is what someone on Name that Plant thought it was as well) -- aren't they considered more or less invasive plants in a lot of areas these days? So I'm hoping for Sargeant crabapple since I wouldn't mind having one of those for the birds (means the little guy can stay right where he is now, in the bird/butterfly garden).

That is not a tree. Looks like Partridge Pea, which is Cassia fasciculata (now called Chamaecrista fasciculata ?), but it is hard to be sure because I can't quite see the flower itself. By the way, chueh, you are welcome to ask questions on the Georgia forum too. Here is a link that might be useful: Georgia forum

Black cherry looks good for #2. The Viburnum dentatum is close, but the leaves are more densely toothed -- about 17/side instead of 9 or 10 per side. I had identified a different plant as "Common Chokecherry" -- rounder, simple toothed leaves, with a cherry-like bark, similar height to the Black Cherries above. However, the fruit come in "sprigs" of about 20, each on an individual stem coming out of a single point. Right now (July 9), the fruit are green and about 1/4" diameter. I'm wondering whether they are something else, whether Crab Apple or something different. Thanks, Jeff