I guess I’m on an improvisation kick this week! As much as I am not a naturally gifted improviser, I have always admired those who were, and I see the value in helping students develop an openness to improvisation. Ever since I started doing student interviews years ago, one of the areas that I include in the interview is a brief improvisation activity. I tell the student that we will play a black key improvised duet. They can play any black keys they want and it should sound good!
I usually give them five style options: waltz, circus, cowboy, flowing, jazzy. Once they pick a style, I start improvising an accompaniment pattern in that style in the lower register on the piano. They are usually a little timid at first, but I gently encourage them to just try playing any black key in the upper register. If they can, I also encourage them to match my beat with whatever they are playing. As they warm up to the idea, they often play with both hands and even try imitating the rhythmic or melodic patterns that I am playing.
As we do this, I watch for three primary things:
- Did they maintain a steady beat?
- Were they relaxed and free in their technique?
- Did they incorporate the specified style of playing?
These are huge musical indicators to me and give me a good feel for the strengths and weaknesses that we will likely encounter in their musical studies. But at the same time, the student has a blast discovering that he can already play something that sounds so good even though he’s never taken lessons before! Of course I praise the student profusely for his musical abilities and both he and his parents leave even more excited than before to start lessons! 
Ooo! That sounds like fun! You should do that with me sometime, and tell me what I need to work on. Teaching myself only goes SO far.
I appreciate your willingness to share the great resources that you do! This may be an obvious answer question, but what do YOU play on the lower register when doing the improvisations, while the student plays on the black keys in the higher register? I would like to start doing this with my students. Thanks again!
I would be happy to do that, Cori!
Thanks for your comment, Kristi! I just improvise a basic accompaniment pattern, sometimes throwing in a little bit of a melody. Waltz would be a 3/4 octave-chord-chord type of pattern; circus is usually 4/4, faster tempo, very staccato; cowboy is a slow, lazy, swing-style; flowing is arpeggiated, legato chords; jazzy is a syncopated rhythmic feel. Hope that helps!