Wise move avoiding the dog park, especially while she is still a puppy, and especially a four month old puppy. While it's good for a young dog to have all sorts of interactions with other dogs and types of dogs, being that you do not know those dogs and it is a free-for-all, it's not a safe or controlled environment. In their lifetime a dog will have some negative experiences, but for each of those experiences, a dog should have several positive ones. A dog park is a crap shoot.
Head off to class and ask your instructor about local play groups for puppies or perhaps make play-dates with some of your classmates with appropriate dogs and puppies.