The purpose of school should be to prepare kids for the rest of their lives, but too often what kids need to be prepared for is surviving the school day itself.
Our culture rightly admires risk-takers, but we need our 'heed-takers' more than ever.
Introverts need to trust their gut and share their ideas as powerfully as they can.
Figure out what you are meant to contribute to the world and make sure you contribute it. If this requires public speaking or networking or other activities that make you uncomfortable, do them anyway. But accept that they're difficult, get the training you need to make them easier, and reward yourself when you're done.
Don't think of introversion as something that needs to be cured.