And just because a person has been in the classroom as a student, that doesn't make them an expert on teaching.
Frankly, I don't consider myself to be an expert on anything. But after 31 years of teaching high school, I hope it's okay to give a little advice to parents of teens.
1. Don't go into a parent/teacher conference with the words, "Why don't you like my child?" on your lips. If the teacher really doesn't like your child, which is highly doubtful, then you don't want to know why they don't like the kid. Trust me on this. It is a boomerang question... In other words, teachers don't (contrary to public opinion) wake up, throw on their clothes, and bust out the front door thinking, "Man! I can't wait for third block so I can dislike Johnny some more today!" They just don't.
2. Don't go into a conference and start bad-mouthing your ex-spouse. In all likelihood, it will reveal more about you than about them. Even if it doesn't, teachers want to focus on a solution to whatever problem exists. Most likely the ex-spouse - especially if he/she is a bum- is not part of the solution.
3. Don't ask your child's teacher to spend more time after school helping them with their reading and neglect to mention that the child is on probation for stealing a car while they were high with their friends. Teachers are worker bees (for the most part) and have chosen a "helping" profession because.. they like to help. Extra tutorials, however, will not help Johnny if he's getting high several times a week outside of class. He needs professional help and Mrs. Jones needs to quit beating her head against a wall after school because of mis-information. (Ditto on bad-mouthing Mrs. Jones to the principal because Johnny isn't doing well in her class when you know Johnny is running around most every night, often one step ahead of the law. Your denial can get Mrs. Jones in hot water and put needless pressure on her while your child continues to self-destruct).
4. Don't go off the deep end if you check ed-line and your child has an 0 or an F on one assignment. Ed-line is a mixed blessing. It can help; but it can also hurt. I graduated from high school and college with honors. However, if ed-line had been in existence, I might never have lived long enough to make it to college. Even the best students can slip up from time to time. It doesn't mean they are headed to Alcatraz; if you are going to check ed-line constantly, you need to keep things in perspective. If your identity is wrapped up in your kid's grades, then limit your time on ed-line or have your spouse check it. Every kid messes up from time to time and their scholastic performance is not to be confused with your identity and your sense of well-being.
6. Don't feel bad if during a conference, your stress spills over into tears. Most teachers have a tender heart and can identify to some extent with your sorrow. If your child is breaking your heart and you suddenly get swamped with grief and start grabbing tissues off the teacher's desk, you don't need to apologize. That happens at conferences probably more often than most parents realize and it's legit in the majority of the cases. Many teachers (yes, even in public schools!) will listen and then go home and pray for your child as well as make an extra effort to encourage your son or daughter whenever they can.
7. Don't believe your child when they come home and say they didn't know they had homework. 99.9% of the time, you will be right to toss that statement right out of the window. (Just as teachers are right in tossing out many of the things that kids say about their parents. It is a two-way street :).
8. Remember that most teachers generally do not go into this profession for the money or for the non-existent "short" hours. They go into it because they love kids and they want to make a difference. Most teachers willingly give of their "free" time before school and after school to do the things they are trained to do - review kids over their lessons, help them develop learning skills they are lacking, and/or help them catch up with work missed while they had a prolonged illness. While they do these things willingly, once your child goes home, the teacher still has a ton of things on their to-do list before they can call it a day. Most of the teachers on my floor arrived at school between 6:30 and 7 a.m. every school day and almost none walked out the door by 3:30 or 4. If they did leave "on time", they took work home with them. So be appreciative of things your child's teacher does and look for ways to encourage them. It won't go unnoticed, I assure you.