Don't know if it's worth pointing out, but a HUGE number of Amazon's reviews of 'Room 13' appear to have come from a primary school class in Worthing in July 2005... all of which are 4* and 5* (possibly at sir/miss's insistence..?) ...which might skew things a little, overall. Jes' sayin'.
Anyway, anyway... I bought 'Room 13' as a potential reader for a special needs English class I teach, and while I enjoyed it, I'm not convinced that it's stood the test of time very well. The kids - apparently urban, northern kids - spend far more time saying 'drat!' and 'heck!' and sucking really enormous sticks of rock than *my* class would find credible. Compared with the grittier edge of Swindells' later stuff (things like the brilliant 'Stone Cold', in particular - still totally relevant in spite of its age...), this comes across as something of an endearing literary anachronism... a sort of late 80's 'Famous Five'... meets 'Rentaghost'.
It's an engaging enough yarn, though - pacy, nicely plotted, a bit short on characters but evocatively atmospheric... just likely to be a bit bewildering for a generation raised on Spongebob Squarepants, Harry Potter and JLS.