Who said girls want to dress in pink and play with dolls, especially when they could be building Rube Goldberg machines instead?That was the message of a video that went viral on YouTube — an ad for GoldieBlox, a startup toy company that sells games and books to encourage girls to become engineers. In the ad, three girls are bored watching princesses in pink on TV. So they grab a tool kit, goggles and hard hats and set to work building a machine that sends pink teacups and baby dolls flying through the house, using umbrellas, ladders, using GoldieBlox and the Spinning Machine ($29.99). The game revolves around Goldie, the girl inventor, and aims to help teach spatial skills, engineering principles and confidence in problem-solving.The ad has generated discussion about a much broader issue: the dearth of women in the technology and engineering fields, where just a quarter of technical jobs are held by women.The ad is set to the tune of Girls by the Beastie Boys, a decidedly anti-feminist ballad with lyrics that the ad's creators rewrote. (GoldieBlox later took down the video after lawyers for the Beastie Boys objected.)The Beastie Boys sang, "Girls to do the dishes/Girls to clean up my room/Girls to do the laundry/Girls and in the bathroom/Girls, that's all I really want is girls."One of the actresses in the ad sings: "Girls build a spaceship/Girls code the new app/Girls that grow up knowing/That they can engineer that/Girls, that's all we really need is girls/To bring us up to speed it's girls/Our opportunity is girls/Don't underestimate girls.""I thought back to my childhood with the princesses and the ponies and wondered why construction toys and math and science kits are for boys," Debbie Sterling, founder and chief executive of GoldieBlox, said in an interview. "We wanted to create a cultural shift and close the gender gap and fill some of these jobs that are growing at the speed of light."Sterling started the company two years ago after graduating with a degree in product design from the mechanical engineering department at Stanford.GoldieBlox toys join others on the shelf aimed at encouraging girls to build things and consider engineering. Lego sells a pink set with a girl character and Mattel introduced a computer engineer Barbie that wears high heels and carries a hot pink laptop.Yet the pink-washing of those toys, including the toys from GoldieBlox, has been criticized for feeding into the same stereotypes about girls that the ad aims to knock down. Sterling said she did not believe pink was bad."It's okay to be a princess," she said. "We just think girls can build their own castles, too."