My son Nicholas is six and, like all children, his questions are endless.

His grandmother was sick recently and we were all a bit worried.

"Mom, why do people have to die?" he asked. I explained that everything dies. I listed examples - flowers, animals - and I said: "People die too. As we get older we die but we go to a nicer place." "Will I die?" "Yes," I told him. "But not for a long, long time, when you are very old." "Will you die? When will you die? Can I die when you die?" The questions came thick and fast. Sometimes I just say I don't know, because it's not good to be caught out in a lie.

They have an insatiable curiosity for knowledge at this age. Their little computer-like minds are always ticking over. Another barrage of questions started about a month ago.

"Mom, I was thinking. How did I get out of your tummy?"

"Em," I said. "I pushed you out." Whew, that was a good diversionary answer, I thought to myself.

"Was it dark inside there? What did I have to eat when I was in there?"

I was waiting for him to ask me how he got in there in the first place. I'm still waiting.

There is no end to his questions - and yet if I ask him anything about school, I get nowhere. It's like a secret club, a taboo subject. I ask if he likes school or if he thinks he is good in class.

"Mom," he says, "don't ask!"

However, sometimes, little things about school slip out in the course of a conversation and you get wise at tapping in to the secrets of the classroom and learn little bits about their everyday school life. "Did you enjoy your lunch?" I asked him recently.

He told me that he didn't really eat it because he gave half of it away to his friend, Thomas.

"We often swop lunches," he said. "Thomas often has crisps." Alarm bells went off when he quietly mentioned a boy who said he had a gun and that he'd shoot Nicholas's grandfather. Again, we hit a brick wall when I tried to probe further.

I generally get more information when I start with a similar line of questions at a later stage. The best time is when the two of us have a little chat at the end of the day. It's not that he's secretive by nature - more like they have a pact among themselves not to tell stories from school.

Whatever you do, you must not tell them secrets. This is a sure way of getting them to blurt something out.

I made that mistake last week, innocently asking him if he knew what I was getting for my birthday. "Well we're not getting you a CD player," he said in all innocence. "Ooops," he added.

Last year I was changing jobs. When I came to the school to collect Nicholas that evening, the teacher congratulated me on my new job. Nicholas, beaming beside me with adult pride, had told her the whole story. I've learned that if you want something to be kept private, you have to be wary of little ears in the background, especially if they are playing away quietly - that's when they are listening most attentively.