You're young and stupid, so here, let me half-ass this issue for you
I just listened to the most recent episode of "This American Life" about people who had firmly held beliefs that they then changed. What was interesting about it was that they didn't actually detail the process of anyone really shedding a deeply held belief, so it was kind of a rip-off. The closest was the woman who came to realize that her ugly-ass super-80s acid-washed jeans did not actually turn her husband on, but the opposite. Which was a great story, actually, and I highly recommend it.
Two of the other stories are fascinating trips into the culture wars, and really the way that people talk past each other. Minds aren't changed in either case. One is a sad story of a woman whose tepid-seeming faith in god disappears completely when her friend dies of cancer, and she faces up to the fact that there's no hand directing the world towards justice. Through a complicated set of events, she ends up on a number of phone calls with an evangelical football coach, who thinks he can just argue her into believing in god with a bunch of half-baked lies and weird, depressing assertions. (The ones that jump out at me were that Darwin caused the Holocaust and that sin brings disease into the world, which is not helpful when your friend died of a disease that's actually caused by mutations in cells.) She is not converted, of course, but I do think she lost another illusion, which is that Christianity had any relationship at all to decency and morality. In this case, it seems religion made this man less empathetic, more callous, and perhaps less moral. She's grieving the loss of a friend, and all he can talk about is someone who prayed away cervical cancer. It's interesting.
The next story was more disturbing, because the tone deaf person that just doesn't get it is a feminist. We expect fundamentalist Christians who believe wack-a-doodle things to be unable to conduct a normal discussion of any issue. But Molly Antopol tells a story of how her mother tried to bully her out of a childish sympathy for pro-life arguments that she picked up in her junior high class. What happened was her teacher decided to have a "debate" about abortion rights in class, and of course, a bunch of kids who don't know much about biology and even less about sex are going to miss the point entirely, and be swept up into sentimentality about fetuses. This is understandable---they're kids. When adults who should know better get into this line of thinking is less understandable, and frankly, I don't buy it so much in adults who almost always know much more about sex, and for whom the issue is inseparable from their disapproval and fear of female sexuality. But I digress. The entire story was a pitch perfect example of how children are introduced to the issue in the worst possible way, and it confuses them, sometimes permanently.
To begin with, having a bunch of 7th graders "debate" abortion rights is like having a group of nuns teach a class in blow job techniques. Anti-choicers thrive best on sexism and sex-phobia, two things that may be reaching all-time highs in your average 7th grade classroom. Junior high and to an extent high school are probably the most sexist environments that people will find themselves during their entire lives, and add to that the conformity pressures that most young people feel and you're not going to have a productive conversation that has anything even approaching respect for the idea that women are human beings with rights. You'd think that school teachers would get this, but many times, no. I recently got an email from a student who witnessed another variation of a teacher thinking putting women's basic human rights up for debate with a bunch of teenagers was a brilliant idea---in this case, the teacher got a class to debate whether or not the rape in "Tess of the D'urbervilles" was actually a rape, with the predictable result of a bunch of belligerent teenage boys trying to bully everyone else into thinking that isolating a woman and then attacking her in her sleep could somehow be anything but rape.* This strikes me as the least effective way to get to kids on the issue of whether or not women are full human beings that deserve all the rights and respect that men get. The unquestioning sexism that rules their world will out most of the time, and no one will have learned squat.
The mother's approach is just as bad, though. Sending her daughter to her room and bullying her into mouthing platitudes about choice isn't the way to address this issue. But the more I thought about this story, the more I realized that the mother was up against the other weapon of anti-choicers---not sexism so much as sex-phobia. Because you can't have a coherent discussion about abortion unless you talk about what the debate is fundamentally about, which is sex. Sex, and whether or not we as society embrace sexual double standards as a way to stuff people into stifling, miserable gender roles that don't do much for them but keep the institutional life that benefits the few at the top churning. And how do you explain that to a 7th grader?
How do you get someone who barely understands that sex exists to see what's so wrong with anti-choice assumptions about the role sex with dudes plays in straight women's lives? Your average 13-year-old just doesn't have the experience to get what's so backwards about statements about how women only use contraception because sleazy men force them to. To really understand the issue of abortion, you have to attuned to all the assumptions adults bring to the table that people who are still in the throes of puberty don't get. Pop culture is saturated in sex, and yet it doesn't really even begin to touch on how it's just part of life for most adults, a treat that's indulged more than ice cream or going to the movies. How do you get a 13-year-old to understand that it's incredibly unfair to use something so woven into the fabric of life as an excuse to take away women's bodily autonomy? The sturm und drang that your average right winger thinks should be part of sex---that it should always be risky for women, that it's dramatic exploitation, that it's prevalence shows that we're a society on the verge of collapse---is so different than how most people (including most right wingers!) experience it. I don't think you can really understand how sexist the anti-choice stance is until you put it against that framework. It's as if we separated men and women who eat ice cream and told the women that they weren't permitted to have full time jobs anymore, and they brought this on themselves for being so indulgent and/or gullible to the claims of the exploitative Ben and Jerry's.
I suppose the only way you can do that is just tell a kid. But talking about sex in the most simple, biological terms with factual references to contraception is already more than many parents can bear. The thick tapestry of assumptions, sexism, sex-phobia, lurid imaginations of right wingers vs. the ordinary lives of most people, and frankly the crazy belief that something as fundamental to life as sex should be treated as an outrageous sin---it's hard to grasp it if you haven't lived a little as an ordinary straight woman with an ordinary sex life who is under attack from anti-choice crazies.
Still doesn't excuse the ham-fisted, totalitarian way the mother approached the subject, of course. I think it does all pro-choicers well to remember that the easiest people to recruit for anti-abortion nonsense are virginal teenagers who can project all their anxieties about adulthood onto the issue, with a heavy dose of help from adults who really should know better. When they come into their own and start wanting to have a sex life more than fearing it, many of them will come around, especially if you've laid the groundwork. But how?
*Yes, I'm aware of the literary use of ambiguity, etc., but in blatant legal and moral terms, Alec D'urberville rapes Tess. Also, the fact that the subtitle of the book indicates that Tess is a "pure woman" is a little stab at Victorian mores that would hold a woman responsible for her own rape in the way that Tess pays.
Sometimes I sit around, especially after reading a spate of dissenting blog comments, and think, "I'm too cynical of a person". 
It's really a toss-up between these two, 
Texas