Hold a general meeting: Tell parents about the books that you use, the syllabus that you follow, and show them some of their child's work. If you don't speak the parent's native language make sure you have someone available who does.
Parent-teacher conferences: By meeting together, they can talk about the child's strengths, weaknesses, and goals to be achieved. Just as in the general meeting, make sure that you have the child's work, grades, and tests available for the parent to see.
Communicate regularly: With email communication is easy. If your email system allows it you can tag the emails and be notified when the parents read the email. Whether you're going to communicate once a week or once a month, be consistent. Avoid sending emails on Mondays and Fridays since these are usually the busiest days. Remeber to summarise what has been done in class and what will be done in the future.
Be available: If parents have questions they should be able to reach you so give them your work phone number and work email.
Stay calm: Parents can get angry over just about anything: the way you teach, too much homework, too little homework, other children, etc. Remember to stay calm and don't become defensive.
Have a time limit: Some parents will wait for you outside class. Be firm and tell them that you have another class / have to prepare class / have a meeting and that you would be glad to discuss the issue, but first they must set up a meeting. This way you aren't rushed and can go to the meeting prepared.
Get help: Sometimes things just get out of hand. If this is the case ask your principal or director for help.
Updated 18 February 2012
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