Practice is a necessary, useful part of learning to participate in musical activities.  Practicing well, with a purpose is vital to making progress.  You are developing and training muscles; you must treat playing an instrument like a sport. 
        We ask that each student practice for 2 hours a week.  Musicians should strive to thoughtfully practice each day.  Even 5-10 minutes of thoughtful practice is vastly better than not touching the instrument that day. 
        Always create good habits!  Poor practice can be detrimental to musical progress.
    Five to six days a week for 20-25 minutes each day will meet the basic requirement. 
       - 3 to 5 Minutes -warm-up: Focus on posture, mouth placement, hands and deep, warm breaths.  Listen for good tone while playing long, low sounds.  Carefully work on developing tongue technique.  Brass: work on lip slurs in the middle to low area of your range.      
       - 5 to 6 Minutes -scales:  Focus on carefully memorizing finger patterns.  The use of a metronome is essential to learning steady time and even fingers.  Practice with and with out tongue techniques.
       - 7 to 8 Minutes -music:  Work on your assigned band music.  Focus on the 'hard' parts; slow down the time & use a metronome to keep steady fingers and tongue.  Play games with it.  (Your band teacher will tell you how.)
       - 3 to 5 minutes -your own 'fun' music Reward yourself for being focused and working hard.  Have some fun with your instrument; remember - always create good habits.
       - 2 to 3 minutes - warm down: - Re-focus what you did on warm-ups.
    Thank you to Garry Wright and Laurel Phillip for this information.