Yes, it matters. You can't use grade A because there aren't so many nutrients, etc in it. I can't find the quote I'm looking for from the book, but here's one to get you started!
Maple Syrup Grading: Grade A, Grade B, and Grade C:
USDA Grade A maple syrup is the most popular grade for everyday use as a topping on pancakes, deserts, and other foods. It is usually made throughout most of the short syrup production season. Grade B syrup is generally made towards the end of the season, as the weather warms towards spring and the trees end their winter dormancy. USDA Grade B syrup is much darker and has a stronger flavor, which makes it more suitable for flavoring and cooking purposes. It is thought that this late season syrup contains more minerals. Grade C syrup is no longer an official USDA syrup grade. For those of you looking for Grade C maple syrup, it is now called Grade B. In other words, Grade B & C are the same.
Yea, my friend had a rough time finding it as well--then she chickened out anyway, lol. I'm sensitive to Sugar
so I'm using the blackstrap molasses alternative, I found that in health food stores. You could always order online for maple syrup.