I liked this show very much, but I had to put my fingers in my ears for a lot of it. In particular, Mrs. Wormwood was screechingly painful to my ears.
I don't know how they allow the children to be exposed night after night. I guess they thought they had to turn things up so the children's voices could be heard, but if everything else goes up too, what is accomplished? The kids were enunciating like crazy, but the distortion from excessive volume overcame all. It's a terrible shame, it's an insult to the talented performers.
I bought the soundtrack of the London production, and I really love it. You can hear the lyrics, the harmonies are beautiful, and Mrs. Wormwood doesn't screech her lines.