I chose Mark Cornell of Groove Duke Academy as my sons trombone/baritone teacher on the basis of a recommendation of the exceptional Edison Middle School band program. My son really wanted to learn the trombone and play in Edisons jazz band and thanks to Marks excellent teaching, he was able to move from the entry level to the middle level of the jazz band with less than a years instruction on the instrument. The audition was highly competitive and thanks to Marks instruction, my son was able to succeed. Mark has also been wonderful in preparing my son for the regional competitions, where both last year and this year he received a first. I highly recommend Mark as a world class teacher of music.