What part of NH are you from? There is a group in Concord that will start running the trails every Wednesday night very soon. I think they're good for 6+. I think there are a few in the group looking to push it a little further on the weekends and would probably be happy to have you join them.
Nate: We have a regular training group associated with the Joe English Trail Challenge in Amherst. We usually run Sunday morning. We are planing to do a series of runs in the Whites this summer if you want to participate. If you are on Facebook, make a request to join the Joe English Trail Challenge Training Group where we will post info on the trips. You might also want to post something to the Joe English Challenge page. https://www.facebook.com/Joe-English-Challenge-635083609878752/