Price was always a stumbling block for me when looking at a fully enclosed, commercial ground blind but then the local shop started carrying the Ameristep variety and I was a little surprised by the price. It was actually "doable".
So, I bought a "Doghouse" blind a couple weeks ago and have been using it on several occasions both for deer scouting and goose hunting (I am not sure if commercial ground blind hunting for archery is legal in PA since the laws have been modified in recent years). It weighs approx. 12 lbs, is extremely easy to setup, has a variety of window setups and is a pure pleasure to hunt out of. Even my big ol' 31 inch draw length fits comfortably inside it...<img src=icon_smile_wink.gif border=0 align=middle>. It is definitely big enough to fit 3 average size adults so your two children should have plenty of room in there. The price was around $150 for that particular model though Ameristep does make an "Outhouse" blind that is slightly smaller in size and yet will still accomodate 2 average size adults. Price is around $99.
Hope this helps.