All you have to do is look at incoming CS major undergrads vs finished degree CS undergrads, or you can look at any statistic at all along a women's career.
Women are leaving in droves. We do not have a pipeline problem. We do not need to get more women in kindergarden interested in math.
We have a toxic pipeline problem, when women are driven out of the industry.
Why? What's the (supposed) benefit?
I'd rather see general improvement on math lessons in school. Most of these lessons are boring, given by boring teacher. I'd be happy if people went out of school simply not hating math (they don't have to like) it. I find this to be much worthwile instead of pushing girls into math even though they might not be inherently interested in it.
The problems in STEM (and science in general) won't be solved by quantity but by quality. (They definitely won't be solved by gender.)
TLDR: Stop focusing on Kindergarden. Focus on the women who have already spent years of their life in tech, and are being driven out. Help these women, by fixing tech culture, so they are not driven out.
"the problems in STEM (and science in general) won't be solved by quantity but by quality. "
I agree. Quality. We need to stop driving the quality, talented women out of the industry.