#1 - Participate
In addition to being a well-informed parent, be a parent who participates. Make an effort to meet your child's teacher early in the year, if only to introduce yourself. Throughout the year you and your child's teacher will have opportunities to meet at parent-teacher conferences and school events -- be sure to attend all parent-teacher meetings as these are sometimes the only one-on-ones you'll have together.
Ask what you can do to be involved. For example, being a volunteer for classroom activities is just another way to stay connected and informed. Accompany a field trip, join the Parent Teacher Association (PTA), help organize a classroom party or donate time or resources to the classroom or grade.