We want kids to explore science and get excited about learning (and doing) it. Given that kids learn so much through play, rather than just by trying to sit still at a desk and to pay attention to a teacher who may or may not convey enthusiasm about science, you'd think that science kits marketed as "play" would be a good thing.

Why, then, am I skeptical about the value of science kits for girls?

Packaging "science for girls" this way is likely to teach girls as much about societal expectations as about science.

There is, without a doubt, a lot of interesting chemistry involved in making soap, perfume, and make-up. However, defining that chemistry as of interest to girls -- especially pre-teen girls -- conveys a message that girls are (or should be) naturally interested in grooming and cosmetics. This, in turn, conveys a message that girls ought to be exfoliating and toning and moisturizing, mastering the smoky eye and the shiny lip, and discovering a signature scent.

Here, I see two messages being sent to girls by gendered science kits.

One is that science is not so cool in itself that a girl would appreciate it if it came in a box that wasn't pink. Instead, science is presented as cool because it can be shown to be compatible with acceptable femininity, crammed into one of the narrow boxes that contain it.

Bath bombs, after all, do not actually explode on contact with bath water.

The other, more subtle, message is that cramming oneself into the narrow box of acceptable femininity is important. This box puts constraints on acceptable appearance (at least neat, if not pretty, fluffy, and glittery), and smell (like a flower rather than a young human), and behavior (interested in making stuff, especially as gifts for others, rather than in blowing stuff up or taking stuff apart to see how it works).

In tandem, the messages conveyed by these kits seem to be saying: you can like science without transgressing the boundaries of acceptable femininity -- but those boundaries are very important, and you would do well to learn where they are and stay within them. Maybe they will convince some girls that science is cool, but if they also convince those girls that they have to perform femininity in such a narrow way, is this a net win?

Here, I think it's worth thinking in the longer term. Will buying into societal expectations about the right way to be a girl help girls succeed in science education and careers? Consider that "the right way to be a girl" has tended to be skewed against showing oneself to be good at math and science in middle school and high school. Consider as well that "the right way to be a woman" has tended to be loaded up with expectations about having and raising children, making meals, and keeping a beautiful house -- duties that rather cut into one's time in the lab or the field, if one wants to pursue a scientific career.

Plus, the phenomenon of stereotype threat suggests that girls and women recognize that society sees being female and being good at math or science as in opposition. To the extent that policing acceptable femininity strengthens this perception, whether on the individual level or the societal level, maybe we're better off not feeding this pretty pink beast.

These kits won't make girls who know that gendered expectations are a raw deal love science.

Amazingly, some of us weren't pretty pink princesses when we were girls.

If we didn't already know science was fun, packing it into a pink box and reassuring us of how feminine it could be would turn us off.

If we did already know science was fun, packing it into a pink box and reassuring us of how feminine it could be would insult us. Why would you think you'd need to give science this particular spin to make us want to do it? Why wouldn't you give us the really good science kits -- the ones they boys were getting as gifts?

Here, the folks marketing science kits for girls are making the assumption that all girls are the same. Assuming that young females are a monolithic group -- especially one whose interests you perceive to be so narrow -- means you are bound to alienate the girls who don't fit your stereotype. And if it's simply a matter of not getting their money because they aren't buying your product, that's one thing. However, if in the process of persuading a girl that your science kit is not for her you are also persuading her that science is not for her, that's a harm it would be good to address.

Even girls who perform acceptable femininity without breaking a sweat may prefer a non-gendered science kit.

I have a confession to make: My youngest child, currently ten years old, is a pretty pink princess. She will wear make-up whenever she can get away with it, and embraces skirts and heels and pantyhose.

However, she would be insulted to get a "science for girls" kit rather than one with more intellectual heft. For at least a couple years, one of her favorite "toys" has been a big set of Snap Circuits, which come in a box that is blissfully ungendered. And, she does plenty of chemistry with us at home, regardless of the fact that to date exactly none of it has been aimed at creating cosmetics.

A pretty pink princess has facets.

Tying a girl's interest in science to acceptable femininity may be a bad strategy if she outgrows acceptable femininity.

I reckon there are some girls whose pretty-pink-princess adherence to the norms of acceptable femininity is so strong that a "science for girls" kit might seem like the only way to get them to even give science a chance. And, in the process of getting groomed, perfumed, and made-up with the things they make with such a kit, they may build their understanding of some scientific principles.

However, if you've gotten such a girl to see science as of instrumental value (in achieving a particular sort of femininity), what happens to her interest in science if she decides that achieving that sort of femininity isn't worth the time or effort? Can we count on that interest in science being robust?

My hunch is that tying science to a broader range of features of our world and of our everyday lives -- features which are not necessarily of interest to just one gender -- would be a better strategy for cultivating a robust interest in science.

Then again, I'm not trying to market thirteen different girls' science kits this holiday shopping season, so what do I know?