2. To prepare the etude, teach NOTES AND RHYTHMS TO THE METRONOME. I don't care how many dynamics you play--the judges always tap their foot to see if the auditioner is on the beat.
Next, put in the ARTICULATIONS! That is the second thing judges listen for. Think about most auditions you hear. Probably only a handful attempt dynamics. Save that for last.
3. Play the numbers. Build up the auditions by giving extra credit or perks to students who audition. Those who make it should get more perks. My kids who make it automatically get the first chairs in band, and keep their chairs unchallenged until after festival. (a couple of months). If you want 10 kids to make it, have at least 20 audition. I like to go to an audition with the top third of the band plus maybe more.
4. Make tapes of the audition music and give them out with the music before summer break. Offer free summer tutoring on the music. Stress scale work all summer. I assign a student a scale a week and have them play it 50 times a day on their own. It only takes 8-15 minutes (age and difficulty factors) and it adds up to 350 times for the week.
5. Let your students know that the world won't end if they do not make it, and that they will be better musicians just by doing the preparations. Be ready to console and break bad news.