When the original building toys known as Erector Sets were first introduced around a century ago, they came with a very specific slogan -- "Hey Boys! Make Lots of Toys" -- which made it clear that girls should stick to dolls and dress up. While there's certainly no shortage of gender-neutral building sets for boys and girls today, the GoldieBlox line is specifically designed to appeal to girls. These kits not only include building materials to craft a variety of products, but each also includes a character-based story, which adds a relationship element not found in many other toys. Girls are challenged to read the story and use the components in the kit to craft a structure that solves a problem -- which may range from building the perfect parade float to assembling a functional zipline.

Resource: HowStuffWorks