Treat home practice as you would regular homework.  There will be a new song or assignment made each class.  At this level, I recommend at least 15 minutes of practice each day.  It is ok if your child would like to practice in five minute increments.  It is best if you can be nearby during the practice sessions to give encouragement or ask for “concerts” often.  Look at your child’s book, music sheets, and pictures of good posture often so you know what to expect as the year progresses.