I think in order to get more girls on your team tell them about how much fun FIRST is. It's not all about building robots. Highlights points about where you travel, who you meet, what you do at competitions, how much you learn, and just the amazing experience in general. The things you learn in FIRST will be with you the rest of your life. Tell them that they don't have to want to be an engineer to be on robotics. Last year in my first year in FIRST, I didn't know much about machinery and tools and I decided to be on the fundraising team (at that time I either wanted to be a lawyer or an accountant). I saw how hard the girls on the technical teams worked and then at the competitions I saw how amazing all these robots were. This year I'm now part of the technical build team and FIRST has inspired me to become an engineer which I had never even thought about being.
So to sum it all up: just highlight points that you think will spark their interest. Tell them that they can do things like fundraising and public relations. Next year some of them might help out with the building
