What about the Extras?

iHP got a great scoop on some info, from an unidentified source, about the extras being used for the Hogwarts Express sequence:

Stuff you might not already know about the harry potter filming. There were 40 extras, all from local schools, paid £35 a day. They were all in normal clothes. The windows of the train had a gelatine substance smeared on it to simulate mist – the kids were all told they couldn’t touch the windows because the film wanted the weather to look misty.

Interestingly, this is the second film to be shot using extras from the Glenfinnan area – but none of the kids involved in the first one made it into the final edit in the second film.