Writer-director-producer Amy Heckerling is known for exploring the teenage psyche with films like “Clueless” and “Fast Times at Ridgemont High.” Current projects include bringing a “Clueless” musical to Broadway. She talked about “Clueless” backstories like why it’s set in the San Fernando Valley, the politics of mispronunciation and the merits of knee-high stockings.

On the first day of shooting, Alicia (Silverstone) was going to debate whether immigrants should be able to come into America — what we call the Hate-e-ans Speech. It was written and spelled correctly (Haitians), but that’s just how she pronounced it. After she did the first take, everybody wanted to rush up to her and correct her, and I had to hold them off because I liked the way that sounded, and I didn’t want her to have any knowledge that that was not absolutely correct. I wanted her to feel completely confident.

With “Sporadicus” (the scene where Cher mispronounces the movie “Spartacus”) — by that time, I wanted to sprinkle a little bit of that stuff throughout (the movie). And it’s not to sound stupid, it’s just that if you’re young, you maybe don’t talk to people about political things or titles of movies (you ) haven’t seen. It’s not stupidity, it’s just that you haven’t been exposed but still having the nerve to talk about something anyway.

I was using the book “Emma” a lot as far as research and structure. At one point, there was a party, and Emma didn’t think she should go because the people weren’t high-class enough for her. I wanted that kind of feeling — what would make her have to go to the party? It would be in support of her friend. And it would be a party she didn’t really look forward to going to. So the equivalent of that would be going to the Valley.

My issues with the Valley are not high-class/low-class. It’s just in a basin where pollution builds up, and it gets 10 degrees hotter than the rest of Los Angeles. So I’m not a fan of going to the Valley unless it’s winter.

Thigh-high stockings are something I’ve always loved since I saw silent movies. The sexy girls would have the stockings rolled over their knees. When I saw “Cabaret,” I think the way Liza Minnelli looked in “Mein Herr” is just as hot as any female ever looked. In the early ’90s, the thigh-highs sort of had a brief moment of being in style. They were out of style by the time we started shooting, but I wanted to use them anyway because I just loved the way they look.

Mona May was the costume designer. There was kind of a grunge movement in the early ’90s that had been taken over by high-fashion people. There was something kind of silly about making plaid high fashion. We didn’t have that attitude. It was more like, “What looks good on them, and what fits the overall movie without being completely clownish?”

All those people are really sweet and they all got along. I just saw this movie of the week about Brittany Murphy and they showed the filming of “Clueless” as though all the girls were being mean to her and I wasn’t even talking to her. This is, like, insane. And then there was this really harsh woman playing me!