When studying scales, we often play a certain pattern in a variety of keys throughout the practice period. This is a good and comprehensive design but hardly the only way. Especially for improvising players, a deeper immersion into a particular key will provide greater command. Pat Harbison told me that he has his students play exercises in only one key for twenty minutes and then improvise in that key (without modulations) for five minutes. The following collection of C major scales from the la...