Dammit! This is what I do. I have to focus!
"Hello, children," I start. "My name is David, and I'm a doctor. I've come to your classroom today to tell you about what it's like to be a doctor." Hey, this is going ok, I can do this.
One little boy puts his hand up. "I've seen a dead person. My granny died at home and I saw her. Have you seen a dead person?" Ah, didn't take long to get on to dead people, then. I quickly skirt the subject, and show them my stethoscope. I get a few up to listen to my heartbeat, thinking that might be fun. Another hand shoots up. "Do you make dead people better, too?" Now what? I look across at MrsRRD for some guidance, but for once she is not any help at all - she is trying hard not to laugh, and the effort is bringing tears to her eyes.
I plug gamely on: "No, once someone is dead, I cannot help them, but I can stop some people from being dead." Shaky ground, this. Why, oh why, did I agree to come here? Surely a policeman is more fun for 5 year olds. And suddenly it hits me. "Who wants to come and turn the sirens on in my car?" I ask. I am quickly surrounded, and we march off into the rain (hats and coats first) and they each press the buttons for the lights and sirens, using up the last of my 20 minutes, allowing me to escape with no more tales of dead grannies.
Back in the car, I turn to MrsRRD. "Never again!" I exclaim. "No," she says softly. "Not after the next three schools I've booked you in for."