This week my eldest son is on a residential school trip in the Lake District. He will be sleeping in a tent, cooking his own food and has been given a schedule that appears to involve long, exhausting and spectacularly muddy days. Judging by how excited he and his classmates were at the prospect of swapping their comfortable home lives for all this, I’ve started to wonder if we parents ought to be insulted. Of course, school trips like these are not supposed to be about en-su