My DD14 went to TechNights, weekly meetings on technical topics for middle school girls, at Carnegie Mellon. Then she decided she wanted to stop, and I was fine with that. Then she started attending a weekly math series, also at CMU, and I support that. I'm encouraging her to look at the STEM areas, but allowing her to make her own decisions.
Her older sister enjoyed science and engineering when she was young. Then it was Theater. Then music/music therapy. I encouraged her to invetigate all of them and decide what she really liked. She ended up founding he Womens Engineering club as a Junior in HS and is now an engineering sophomore at a top 10 school. If she had decided theater was her thing, I would have supported it the same. [with multivariate Calc and Thermo next semester, let's see if she decides Theater actually wasn't all that bad.
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As noted early in this thread, there's a difference between exposing/informing and mandating. Having girls miss out on something they would enjoy because they don't know about it is similarly bad to forcing them to do STEM when they don't want to.
