For these girls, tech is a rewarding challenge

It’s an unusual scene for Silicon Valley: a conference room packed with programmers, business developers and app makers rubbing elbows and talking code — and nearly all of them are women.

Thursday night was the final award ceremony of the Technovation World Pitch competition, the largest tech entrepreneurship program in the world for girls. More than 400 teams of middle- and high-school students from 30 different countries around the world competed.