I suggest the following - please adapt it freely:
"Next week we will be visited by a team of people in undertakers' suits who will visit classrooms, talk to teachers, and read working documents.
"Please be courteous to them as you would to any outsider visiting the school.
"Remember they are only doing it for the money, they don't have recent experience of teaching children, they don't understand our school or live in our community, and they have to please their politically sensitive bosses.
"If they had a sense of vocation they would be teaching here; what fun you would have with them then!"
25 Hawden Close