The things that didn't ring true spoilt it for me. The teachers were far too chummy with the children, and the giggling at the way things used to be done seemed at odds with the point of the programme. It may be the way they interact now, but wouldn't have been in the 19th century.
I have only seen the first two episodes this time round, but saw it when it was first broadcast. My school years were in the late 60s/70s, and I think that episode did bring back memories, but I hated school, so they probably weren't happy ones.