Massillon Perry hosts a 9th-10th grade only invitational the last Friday of April. I've attended that meet before, and I can say that 9th-10th grade does not necessarily mean JV. Most of the meet records are pretty good.
Smithville hosts a 9th and 10th grade invitational the Monday of the week that most schools have their league meet. Although not restricted to freshmen and sophomores, Mentor and Woodridge host JV invitationals the same day as Smithville's.