No Hands on Assistance = No Interest?
"The results would appear to counter the notion that female students lack the interest or ability to pursue STEM training, at least at the grade-school level."
I've looked over the NAEP data with their TEL profile tool, and can see no way to correlate "interest" with "ability". Clearly women are quite capable, but this test says little to nothing about female interest in Tech/Engr. One interesting bit: while most points are but a few point off from sex 2 sex, one question was 14 points in favor of males - "Definitely can use tools/materials to fix something".
This metric I can easily believe, given that most fathers have generally favored giving sons hands on experience with tools from a very early age. Computers are tools; take my misspent youth modding Commodore 64's with fellow male peers, most lamenting the lack of female presence capable of even turning a screwdriver. The few women in tech I've met in 25 years, have attributed their interest to early and continued exposure to tools and early instruction from their caregivers. Jeri Elsworth begged her father to have the C64 originally purchased for her brother; her father encouraged her to tinker with car parts he brought home. Other times, its pressure from that EE/ME/tech parent like Marissa Meyer.
I personally was hit with both: a father (electrical engineer) who taught me to use a soldering iron at age 6 (lest I burn down the house), gave me free range to his personal library, and allowed me use to tools in his wood working shed (provided I ask AND put them back when finished). I've now a young daughter myself not quite a teen, and while she prefers her stuffed animals and dolls, I try to give her opportunities with a socket wrench, drill, soldering iron, o-scope (with supervision, of course, even if my wife still worries). It's about familiarity & building confidence; without it there can be little potential interest in the future, even if otherwise fully capable in math/science/engineering.