Uh well, along with others I'll just share how I differentiate them since both are common where I live.
3 Ways
1) if you can get a good look at the tail, think croW = wider/more or less even at the bottom, raVen = V like at the bottom (or diamond as a whole) but it's just a mnemonic and makes more sense if you see this http://naturemappingfoundation.org/natmap/images/drawings/ra...
2) Their calls are very distinct, hear one then hear the other and you won't confuse them atall but that requires having heard both and knowing which is which and I won't even bother to try to explain, you can find a million videos/etc. demonstrating if you really care.
3) Beak, ravens have a slightly curved tip usually and crows... don't but it's hard to see this because of the color, so again, depends on what you can observe
3 Ways
1) if you can get a good look at the tail, think croW = wider/more or less even at the bottom, raVen = V like at the bottom (or diamond as a whole) but it's just a mnemonic and makes more sense if you see this http://naturemappingfoundation.org/natmap/images/drawings/ra...
2) Their calls are very distinct, hear one then hear the other and you won't confuse them at all but that requires having heard both and knowing which is which and I won't even bother to try to explain, you can find a million videos/etc. demonstrating if you really care.
3) Beak, ravens have a slightly curved tip usually and crows... don't but it's hard to see this because of the color, so again, depends on what you can observe