There is a great article in The Nation from a couple of days ago on the importance of the types of toys that kids grow up playing with, and the impact that that can have on their eventual career choice.

"When schools fail to spark children’s interest in science, math, and computing, the result is that populations that have historically been drawn to those fields—the sons of college-educated parents—continue to excel, while girls and low-income kids lag behind. The toys kids play with at home matter, and so do the lessons children learn at school; in order to overcome overwhelming cultural conditioning to the contrary, both parents and educators should actively send the message that all children will have fun and learn a lot when they “tinker” in the physical and electronic worlds."

"Beyond Pink vs. Blue" http://www.thenation.com/blog/165378/beyond-pink-vs-blue

I sometimes hear people say that toys and gender really isn't that big a deal and that kids can work it out on their own. The study described in this article points to a different conclusion - that kids have a tendency to police gender traditional gender norms on their own, which can be a huge detriment as they grow up when the boys have a big developmental headstart in cognitive areas important for spatial reasoning and other skills for the science and technology fields. One message to take from this study is that it's very important to encourage children to play with toys that are traditionally associated with the other gender.