Mansfield F&G may fit that bill, HOWEVER there are NO indoor facilities of any kind as of now and even when the building is occupiable (hopefully by Summer), there will likely be no indoor range for many years to come (due to $$ issues - sorry that is just hard/cold reality as everything is being spent on getting the building occupiable).
That said, the outdoor ranges are decent and the rules allow a lot of latitude that most clubs disallow!
Due to no indoor facilities, the junior rifle program is only held from Spring thru the Fall each year, but it is an excellent program where participants get an opportunity to excel and get recognition with awards based on their progress.
If you'd like a tour (with your Family), just send me a PM or Email.
www.mansfieldfish.com but be aware that many changes have occurred and will be occurring thru the Spring to add features (e.g. picnic area, archery range, new shooting benches on the 100 yd range, improvements on the berms, etc.) thanks to some active Eagle Scout projects that are happening there. So the pictures on the website do not reflect what is currently there (currently much nicer than the pictures show).
A bit of a trek from N. Cattleboro, but OCSA in Pembroke has an EXCELLENT youth program (including Nationals and Olympic competitors,) yd heated outdoor rifle, 100yd outdoor pistol, 50' indoor (non-jacketed pistol calibers only) and great 5-station and skeet facilities.
Massapoag Sportsmens Club. We are in Sharon on the Canton border. Been around forever and have 3 skeet fields, one trap, indoor and outdoor pistol and rifle ranges and also two archery courses. Come check us out. Always someone at the skeet house on Sat or Sun between 10 and 2 or 3. People have their kids shoot here but I am not sure if they have a kids league. Call or stop by. I have no kids of my own so never thought to ask.