Board Thread:Questions and Answers/@comment-24487529-20150302230813/@comment-24487529-20150303215715

Sasha's reference to their ages came from the English localization of the light novel, ("There are around twenty children living in this church, from elementary- to middle-school age", near the bottom of Page 158 of Volume 2) and doesn't make any reference to their ages or school levels in the anime. Of course, she may not know their accurate ages, as you said.

My question was less about whether they were falsifying their ages to get around any sort of NerveGear restriction, and more related to whether it's unhealthy for them to be playing it (obviously, apart from SAO being a death game).It's also less about how the rule is enforced than whether it's not recommended or forbidden for young children to play with the NerveGear.