Looks like you have some pretty decent flint- and maybe a worked piece or two. But the fact that you've got flint is a good sign if nothing else. That one piece that's alone on white...maybe. Hard to tell from the pics. The striped pieces look to be bits of brick. If there are particular pieces you want an opinion of, you'll need to take closer, sharper pics. It's hard, but if you use macro (tulip icon) it'll help a lot.
Keep in mind too that you're looking through a pile of stuff your g-pa moved, so there are bound to be a bunch of broken pieces due to the machinery be it plow or back-hoe or whatever. If I were you, I'd keep looking at the flint and chert- the black material you've found. And once the ground is thawed out and you can hunt a field or creek nearby (if there is one) you'll have better luck.