A previous poster mentioned flying out of NYC area. A few years ago we did this for the April vacation. I'm from Cape Cod, and although it wasn't ideal it wasn't too bad-honest! That trip was to the west coast to DL, and I think we made plans only a couple of months in advance( which didn't help finding flights cheaply), however going on Jetblue from JFK saved us each $1000!! Driving to JFK didn't seem too bad for a $3000 savings! We drove down Friday night stayed in a hotel & flew Saturday.
Another time I had flight vouchers for USAir, but it was February vacation, and same issue, well I found a cheap flight out of Philly, so I took the Amtrak from Providence to Philly, went sightseeing that afternoon, and flew the next morning to LAX. The way home I was able to get flights into Boston at a decent price, so we flew nonstop home. Amtrak was inexpensive if booked a few weeks in advance . The NE ended up getting a snowstorm that caused major delays& cxls, philly was spared and the trains were full capacity.
And FINALLY, my latest unconventional trip.....I found $15 flights on Frontier from Trenton NJ, the drive was just under 6 hours, the airport makes Providence & Manchester look HUGE. A checked bag was only $25 , but we only went for a couple of days and packed a backpack. Only aggravation was the George Washington bridge going down. There was a Courtyard outside the entrance if you went day prior. Would I do it again??? YES if the flights in NE were high and I really wanted to go away. NO if I could get flight for less than $400 RT during peak times (school vacation). I have also flown close to mid week during vacation weeks, and returned mid week the following week for great airfares, but it requires missing school. As my son gets older (6th grade now), pulling him from too much school becomes more difficult.
We are going away for Thanksgiving ( have for years) and always get flight from PVD for about $100 each way, we fly out either Tues or Wed night and return the Monday. Unfortunately I NEVER get lucky with Feb or April vacation
Worcester is another option with Jetblue, but I'm sure that's also high. Allegiant is now flying from Portsmouth NH, and has some good fares, but may be challenging that week.
Good luck - let us know what you find & decide to do!!!