I was at my mother's for Thanksgiving. My sister is always there with her boyfriend, kids, and dog, and my mother's husband's daughter comes with her four sons, in their twenties and maybe early thirties now, and her husband. I gave the lesson in question to one of the sons (and a different one later to the oldest son - things just worked out that way).
I play a lot of instruments. Not all of them well by any stretch of the imagination, but I've played at least ten instruments in public without embarrassing myself. I've noticed that people who don't play think that playing multiple instruments is something mysterious and really difficult. It's not. Getting good on a lot of instruments takes time but picking out a tune on a lot of them is actually pretty easy.
[NOTE: After writing most of the post: If you're reading this on a tablet, this post will teach you how to play a basic song on your tablet. I didn't know that when I started writing.]
The biggest obstacle is actually producing a note at all, depending very much on the instrument. Playing a flute means getting the blowing across the hole to sound right, something I've never been able to do, even though I can blow across a bottle and get a sound easily. Playing reeds involves getting the note to speak at all, preferably without horrific squeaks. Same with brass, though in that case what note you're playing depends on what you're doing with your lips - the determination is not strictly with your hands. Playing fretted string instruments means pressing the string with your fingertip just past the fret away from the body of the instrument and having your finger come in at a steep enough angle not to touch adjacent strings because your finger will deaden them. By the way, with steel strings that hurts at first. (Actually, if you don't play a lot, it continues to hurt.) Not that I play most of these families of instruments, but I've tried most of them at some point.
Making some instruments speak is easy. Keyboards, for example. Percussion, including pitched mallet instruments like xylophones. Recorders and tin whistles/pennywhistles, which is why recorders are often taught in schools - that and plastic ones are cheap and don't lose their tunings.
A lot of people hate recorders because they've heard a classroom full of elementary school kids playing soprano recorders in unison, a sound like a very loud hive of angry bees. An alto recorder played alone or with other instruments can actually be quite pretty. Bach wrote for them a lot, for example in the Second and Fourth Brandenburg concertos. (See YouTube, but listen to versions using original or authentic instruments or you'll hear those pieces played with modern flutes, which sound completely different.)
The lesson? I took two instruments, in this case a melodica and a tin whistle, and I taught a non-musician how to play a simple tune on both of them within fifteen minutes. Actually more like ten. He thought playing a lot of instruments was really difficult and I wanted to show him how that worked.
I chose Mary Had a Little Lamb because the song has all of four notes. On a major scale, it doesn’t matter which scale (there are twelve - actually more than that, but the additional ones are just different ways of notating the same notes), the notes are the one the scale starts on, which I’ll call One, the next one up, or Two (technically a major second from the root note, hence "two"), the major third from root note, or Three, then skip the fourth and go to the fifth above the root, obviously Five. The sequence of notes in any key looks like this:
3 2 1 2 3 3 3 pause
2 2 2 pause
3 5 5 pause
3 2 1 2 3 3 3 3 don't pause
2 2 3 2 1
In this case the whistle is in D Major and my step-nephew wanted to play the tune in the same key on both instruments, so the notes are
On the keyboard, easy to figure out by looking at any keyboard diagram. I published some on my old music theory series here, but searching for one is easy. Here's a link to one:
Or someone like Ron will probably come along and publish one in comments. I'm on an IPad. If I were on a laptop, I'd do it myself.
Right thumb on D, index finger in E, middle finger on F#, pinky on A. You don't even have to move your hand. Or hunt and peck. Just follow the above sequence.
If you want to make it even easier, if you use C, F, or G as One, you can use all white notes, or if you use F# as One you can use all black notes.
A lot of people have a keyboard handy. If you don't, on a tablet you might even be able to download one physically onto your tablet that works. Here:
The F# isn't labeled. It's the black note between F and G. Either octave will work.
Most people don't have tin whistles handy. I happened to, and mine is in D. What I'm about to describe would work on whistles in different keys, it's just that the song won’t be in D Major. It will still come out right, though.
I'll describe what I did with the whistle. If you have your kid's plastic recorder from school, I'll give you different instructions below.
A tin whistle has six holes. You cover the three closest to the mouthpiece with your left hand and the other three with your right. The technical issue is to cover the holes with the pads of your fingers, not the tips. And make sure you seal each hole or it won't work. Blow gently.
Cover all the holes for One. Uncover the bottom hole for Two. Uncover the bottom two holes for Three. Uncover the bottom four holes (right hand off, ring finger on left hand also off) for Five. Blow and follow the sequence.
On recorder it's different. Playing in D is more complicated on a recorder, so this will come out in C on a soprano, but will work on any recorder.
A recorder has a thumb hole on the back and seven holes on top (two of them double but that won't matter). The left hand covers the thumb hole and the top three holes, the right hand covers the lower four holes. For this song, your left hand covers all its holes and doesn't ever move. With your right hand, make sure you seal all the holes, even the double holes.
All holes covered for One, bottom double hole uncovered for Two, bottom two double holes uncovered for Three, all right hand holes uncovered for five. Again, blow gently.
There it is.