- Climbing up the curtains.
- Climbing up and scratching the door frames
- Jumping from the book case's highest shelf down on his desk.
Exercise is difficult too, as humans are naturally indolent. They will spend hours staring at a screen and only drastic measures such as lying on the keyboard will successfully get their attention towards you. So first, you have to get their attention.
Even the stupidest of humans usually notice climbing up the curtains and your other activities. Most will spring into action in a vain rescue attempt (either to rescue your or the curtains!). I fear you may have adopted a human nerd, halfwit or a dingbat, as Oz cats call them. These humans are to be pitied not punished. It is not their fault they lack the ability to understand us properly.
You will have to accept that you cannot change him. Don't cease your activities, as this is good exercise for you. One of my achievements was to rip out all the lining from a pair of curtains: it was a truly satisfying achievement - as you can see from the photo on the right.