M.R.
I would check with the teacher and ask her. He will get the "hang" of the suit if you give him time and the teacher should be patient with him. I'm from the Rochester area, not Cooperstown, but we get some nasty spots in our winters, too, and we end up with the snowpants. Our snowsuits (or maybe what you mean by pants?) are just the bottoms with the bib top and straps over the shoulders. If that is what you mean, I love those here in the winter--they cover the gap between the shirt and pants under the winter coat, which is great for active kids outside. He will figure them out, even if you leave the buckles on and let him pull the straps over his shoulders. If the boots have fleece lining and are somewhat water-resistant, they should be fine. I usually end up with one pair of boots for my kids in the winter here and double up the socks if needed. I need to invest in winter boots for myself but usually just double up my socks and let my toes freeze in my sneakers. One of these years... I also only use the snowsuit for outdoor play--if they are just going to the car and back I just put them in their coats.
Welcome to NY!!! =)