My Milana is also leash a puller - I have not tried any classes but employed a few techniques suggested on this forum. Unfortunately, she is still a leash puller. However, I do recommend getting your puppy a safe harness. Milana would pull so hard that she would start coughing (and I have always used harnesses). I tried all harnesses but nothing is comparable to velcro choke free harness. Now that we use this one, even though she still pulls pretty hard - at least she is not choking or coughing. I got it from Shinja (Lil Sis) on this forum.
In terms of pulling, I am still trying to solve this problem. She is not aggressive but she wants to meet every single dog and human, and this just gets annoying on our walks
Maybe I'll try walking in a different direction as suggested by the previous poster.