Dreadful!ly acted is pretty damming considering the children were 9 and not paid
To be fair, the kids aren't the problem as most of their dialogue comes in the form of voiceover, it's the parent characters (the woman playing the mother in particular).
There's clearly a lot of investment gone into the production, just the iPods and headphones alone amount to a small fortune (although I guess they can be reused in other productions), so I think it's a shame that they scrimped a little in using volunteers rather than paying the fairly minimal cost of hiring a couple of jobbing actors for a day or so as it has had a significant impact on the overall quality of the production.
No offence intended to your son, Grove, but I stand by my original comments. I actually didn't think it was a bad review!