(1) New piano student.
He called me a few days ago and we talked about what he wanted to do. After talking for a bit I knew I could be a good instructor for him and he felt the same way, so we scheduled a lesson.
When he arrived today, he brought his Mac, played some recent tracks he wrote and told me what his compositional difficulties were that he wanted to handle. By listening to his "products" I knew exactly what he needed to do.
I put him on the piano and assessed what he knew and could do (or not). After some more inquiry I found what he didn't know, but needed to, and designed his program from there.
His lesson entailed some piano technique, that we spent at least 40 min on, a tiny bit of music theory clean-up, (clearing up some confusions and unknowns), then some application steps with a few musical basics.
That was enough for the first week. Not too much and not too little.
(2) Upright bass student
He came wanting to know what he needed to do to take his playing to the next level. He already plays electric bass semi-professionally, and wants to start doubling on the upright. OK.
We talked over the immediate goals and went to work. I checked out his basic technique, discovered that he had already tried one of the fundamental upright bass books, "Simandl," and off we went.
I started him with basic technique for plucking and positioning the instrument. It's a big thing and you have to get the balance and height of the instrument just right. Then we worked on left-hand position and right-hand position, then on the intonation exercises. Intonation is crucial on a fretless instrument.
I gave him a bunch of "standard" technique exercises, that I had earned from my many upright teachers, then assigned a number of pages in his Simandl Reading book to drill before his next lesson.
No theory to clear up, no composition stuff to delve into: just a "straight ahead" upright lesson.
Two very different lessons! This is why I never get bored teaching. Everyone is different.