Gossip about schools dates quickly. Heads usually move every 5-10 years; there is a complete change of pupils every 6 years or so; and there are often structural changes (eg single-sex schools becoming co-educational). But reputations can live longer ('the school where the first eleven torched the cricket pavilion'), so treat grapevine information with caution.

A parent with a child currently at the school can give you contemporary low-down but their view of a school will be coloured by the very personal experience of their child, which may or may not be relevant to yours. Prep school Heads should be up-to-date and may be more objective than parents.