Script advice. Filler scenes

Hi I was wondering if anyone could assist on the script guidelines for 'filler' scenes (not sure what they are called).
I mean the scenes which have no actual.dialog but help set the mood or location of the next one.
An example of such would be, a scene takes place in a classroom and contains dialog. The scene before was a shot of the school, then a shot of a corridor with kids walking around, then we head into the scene with dialog.
As a writer do you have to include these additional scenes in the script writing process, or is this left to the director to decide what shots would work?
Hope this makes sense.
Any one have any experience in this?

They're called establishing shots and you only need them if they help tell the story.
The director may well add them later, so that the viewer can 'establish' where they are.
But the script 'reader' doesn't really need them as the have the scene headings (INT: CORRIDOR, SHOREDITCH HIGH SCHOOL - DAY) to tell them. They are only of use to the writer if they help set the scene - ie it's a run-down inner-city school, or a posh private school - and then doesn't need saying again. And as you say, if a certain mood needs setting that has relevance to the following scene ( a dark and stormy night etc etc.). Sometimes, after a particularly frenetic scene, a little moment of calm can be helpful to the read. But the general rule is less is more, and any establishing shot scenes should be as economical as possible.

Of course saying SHOREDITCH HIGH SCHOOL doesn't set the scene if there are two schoois shown in the programme (and even having a non-uniform class at school and a college might be confusing). You're going to need to establish that it is Shoreditch or a High school some other way.

I feel so stupid now.

Ha ha.