I'm a newish instructor doing mainly trial lessons. Are they all the same? Most definitely NO!!!!! Here's a rough sample, and they've all happened:
1) He/she doesn't really want to take control, so you get to practise absolutely anything you like. Though if they're nervous, don't overdo the fancy stuff.
2) He's desperate to fly, but totally clumsy and cack-handed, and you need faster reactions than you ever believed possible.
3) He didn't tell you he's a f/w pilot and has had a few unofficial goes at flying a helicopter before. He picks it all up extremely fast, quickly gets bored with flying straight and level, and you find yourself teaching and demonstrating a whole bunch of stuff you hadn't prepared.
4) He's read a lot, heard all about autos, vortex ring, and so on, and would like everything demonstrated, please. And he'll ask questions non-stop while you're doing it, and expect instant answers.
5) He's the model student, does it all as you would expect, and at the rate you would expect, behaving exactly as you were told on the course that students would. Er...it may be wishful thinking, but I think I had one of these....once!
6) He's absolutely plain bloody terrified, and wants to get back on terra firma ASAP if not faster. You talk to ATC, try to calm him down, and keep an eye on what his hands might do in case he freaks out, while wanting to get down smoothly and slowly, as an auto is hardly appropriate as it will scare him more. Only had this happen once, but I am fairly new!
I'm sure there are loads more. This is in my first 30 or so instructing hours, as I'm only part time, and most of them are half an hour or less, so it takes a lot of time to get many hours. But am I getting experience? Well, what do YOU think?