This problem is not something you're alone in: I've fought with it off-and-on for all three years I've been on the team. It's difficult sometimes to earn the respect you're due in a team of all guys, but it IS possible.
My very first year of robotics, I wanted to be on our VEX subteam for our local robotics competition (not FIRST). All of the other members were boys, including the VEX captain. After a few weeks of slowly getting acquainted with robotics, I realized that our team wasn't doing so well due to his weak leadership skills. So, after speaking with our coach about my frustrations, he told me, "If you want our team to do better, why don't you take over as captain? I know you'll do well, and I'll support your decision either way." The following week, when our ex-captain arrived late to the meeting, he learned of my takeover and was positively freaked out by it. But you know what? We worked twice as fast under my leadership, and had a fully operational VEX robot by the second tournament.
My second year, our team incorporated a student government, and I was elected as Secretary. I worked so hard that year, because I wanted to prove myself capable of taking the Presidency the following year. Now, here I am: Madame President of team 3641.
I concur with the previous posts; get help from your mentors/coaches, and use facts to back up your ideas. Although, I know firsthand that sometimes not even those options will work. Honestly, for things like fundraising opportunities, you just need to take the initiative. If your team is not listening to your ideas, why don't you just
enact them? Go out and plan these events on your own, then come back to the team and announce, "Hey guys, I've set up an event at ______, so be there by XX time or else you won't get fundraising credit." In an aggressively male environment, you just have to play by their games, only better. It's all about out-stubborning the male ego.
Hope this helps!
I've learned everything the hard way, as I was once a shy and submissive girl, and now nothing can tear me down!