How long have you been playing?” asks Phil, a gloomy world-class jazz pianist.

“Well I played classical piano as a child and recently started taking jazz lessons so that I could help my son practise the saxophone,” I tell him. “It’s going really badly.”

It’s a Sunday in August and my son Nat and I are registering at the Jamey Aebersold jazz improvisation summer school; a high-risk proposition for both of us. At the age of 10, Nat is the youngest student and has been playing for less than a year.

Although it claims to cater for all ages and levels, the course is no more aimed at children than sandpits are at the elderly. On the face of it, I am a more likely proposition. Unless you play to concert standard, which I don’t, the piano is a lonely instrument. Jazz offers more of a chance to play with other people.

There are about 120 of us. Some are teenagers – boys with swept-for-ward hair and girls in tiny skirts and ballet pumps. But most will not be seeing 40 again: a professorial type in a crumpled linen suit, steel-haired men in Hawaiian shirts and rather fewer middle-aged women. The air is vibrating with the sound of instruments being warmed up; it’s like being in Fame without the legwarmers and with much older students.

Monday morning kicks off with our first theory class. Aebersold himself takes us through the types of scales – there are at least 15 compared with classical music’s standard three. Some have weird sounding names; “dorian”, which could be a Greek temple, and “mixolydian”, which I had thought was something rabbits suffered from. Others are all clues; “half diminished +2”, but no easier to decode. Combine all this with the 12 different keys and classical music is beginning to look like the version for simpletons . . .

Nat joins me at the break looking perfectly cheerful – either his crisp young brain is finding it all easier to take in, or his class just is more elementary. Then the whole school gathers for Jamey’s jazz musician-ship class – 90 minutes that combines rather brilliant analytic breakdowns of great jazz solos with lots of folksy wisdom: “Practise, practise, practise”; “circle of fifths” (don’t ask); “Here is a picture of a great jazz trumpeter/saxophonist/pianist who died before he was 45 of drink/drugs/ cigarettes/all of the above”; ’”Fear is the greatest handicap” etc.

There are seven pianists in my group, including a scary 14-year-old prodigy and an elegant silver-haired lady from Hampstead. Today we are going to work on Satin Doll– a basic 12-bar blues. We start by laying down the chord progression with our left hand. Simple enough, but it turns out that in jazz the key might change in every bar. After an a hour and a half I can more or less follow through the sequence with the playalong tape but only if Phil is shouting “two, three, four TOP” at the end of every 12 bars.

We break for lunch and then it’s back to our groups for a piano master-class with Dan, an even more lugubrious version of Phil and every inch of what you might expect of an American jazz teacher – all shorts, socks, sandals and grizzled beard.

In the last session of the day we go back to Satin Doll adding to our chord progression, first the tune and eventually our own improvisation. And this is when I start to come unstuck. The tune for the right hand is written on the left hand page and the chord progression for the left hand is to the right. I am used to seeing bass and treble written one on top of the other and this crazy illogical arrangement is making my brain strobe.

By Day 2 I am in a terrible funk. I have remembered that I don’t actually like jazz. I particularly don’t like the bit where they come away from the tune in individual, apparently unrelated, little solos, after which we are meant to clap. How on earth did I manage to overlook that improvisation is exactly what this course is all about? Nat on the other hand is having a ball. He seems to have made friends with everyone, total strangers keep telling me how brilliantly he is doing. How can it be so much easier for him than for me? Well partly, I reflect sourly, because the saxophone is much easier. You can only play one note at a time.

By midweek I am in a bad way. My eyeballs and shoulders ache. My evenings are spent horizontal, watching TV medical dramas, but I can’t sleep because I have tunes and licks running inside my head. Even Nat, who is still raring to get going every morning, is sleeping for ten hours a night, but looking more ashen by the day.

The atmosphere is unlike school in that we are collegial and uncliquey. “How’s it going?” we ask each other and then compete about who is feeling more dispirited and humbled. “I realise I am still in the nursery,” says the linen-suited professorial type who turns out to be an Irish factory worker. If that’s true, I haven’t yet been born.

But I am beginning to have tiny epiphanies. Certain things that I have heard enough times are beginning to sink in and almost make sense. I am getting a feel for the music I am hearing and in doing so I am very nearly enjoying it.

Thursday brings a rising note of panic. The week ends with a concert and each of the combo groups will perform a number with every member taking a turn to improvise for 24 bars. By Friday morning it has become clear to me that it would be a kindness to the audience to sit out my solo. I tell Phil that I am going to exercise my prerogative as an adult and not play, but he is so sweetly insistent and reassuring and, above all, I can’t bear the responsibility of adding to his sorrows, that I cave in.

The concert is sensational. I can’t believe how wonderful everyone sounds. I even love the improvisations. I actually get the point of jazz for the first time. Nat, whom I had assumed was coming in for so much praise because of his youthful cuteness, really was fantastic. And the sight of him on stage surrounded by huge grown-ups, some of them heav-yweight professional musicians, tapping his little foot and performing a perfectly convincing solo was a top parenting moment. And my solo? I wish I could say that it was like the movies when the little guy brings the crowd to their feet, dancing in the aisles. But it wasn’t. It was the opposite of that. It was not-know-where-to-look, laugh-out-loud bad. (“What happened Mum?” Nat said. “I thought you were having a stroke on stage”). But here’s the thing. For a couple of bars, at the end, I was in there, I was really doing it. Or who knows, maybe I wasn’t, but I felt I was and it was incredible. And even though I should have slunk home that night covered in shame I actually felt a kind of heady exhilaration.

Would we do it again? Nat can’t wait and has become umbilically attached to his sax. Jazz probably just isn’t for me, but I might stay with it a while; I can play some quite difficult pieces of Mendelssohn, make a haddock soufflé and follow a knitting pattern. Surely it can’t be beyond me to play a simple 12-bar blues?

Jamey Aebersold returns to Britain for The Jazzwise summer school 2008, from July 27 to August 1 at Richmond Adult Community College, Richmond. Details: jazzwise.com

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