Problems with mise-en-scene in the filming

We are planing on basing our video in a 6th form collage, although we are filming in a secondary school. We have some shots of students entering the school with lots of people in, and these shots will be much easier to film if we take the shots as the school day begins. The problem is that most of the actors will be in school uniform, and this will seem unrealistic because it will be obvious that these people are not A level students.

To tackle this problem, we will try to take these shots on a school mufti day so that everyone will be in there own clothes.