I think fundraiser are a better options, like a car wash or asking for a donation for a yard sale or a raffle.
I have to gather donations for my highschool cross country team. Who do I ask, and how (should I suggest an amount such as $10)? Should I even ask acquaintances/near strangers for a donation?
They want you to ask for cash donations? Really? I think fund raisers are a better option. Like a carwash, or asking for a donation for a yard sale.
"Hey, my school is raising money for the cross-country team. Can you donate a few bucks?" as Normal Nobody suggested.
Not bad at all. I might rephrase the second sentence to "Can you help us out?---we even like pennies."
And I might try give them some useful information, such as the fact that the time frame between actually needing the money and finding out that you will need it is too short to organize a standard fundraising project---that should answer all the unasked questions they might have.