Note Length Exercise 2: Mixing It Up
If you can do all of Note Length Exercise 1, try this next one. Basically, this exercise is all five parts of the previous exercise played one after the other, without stopping. Choose a tempo at which you can play the 16th note exercise (or the 8th note exercise, if you are having trouble with 16th notes). Play this entire exercise without speeding up or slowing down. Your foot will tap at the same tempo the whole time, while your hands play notes of different lengths on top.
Note Length Exercise 3: Making It Your Own
Try improvising using these rhythmic concepts. Set a tempo, and play notes of different lengths on top. For each beat, you can choose a different note length to play. If it helps you to plan out what to play before playing it, you can do that, but the goal is to be able to improvise. Start by improvising something easy. For example, you could start by just using quarter notes and half notes. Slowly add in 8th notes and 16th notes until you can switch between all of the note lengths at will.
You could also improvise without thinking about which note lengths you are playing. Simply set your metronome and play with rhythm. Can you find rhythms that you enjoy playing?