There are nine units in this book, starting with the basic blues scale in C, then moving to the keys of D, G, A, and E. Each unit has four parts: a blues scale; an illustrative short original piece; a riff improv" where students can combine riffs in any order; and finally, a free improv that allows students to use riffs already learned as well as improvise new ones. This step-by-step approach ensures progress, always building on previously learned skills. Includes recordings, and MIDI files are available as free downloads below."