From the personal-finance duo Fortune magazine called "funny, smart, cynical, and] opinionated" comes savvy financial advice for today's street-smart young investors. The Motley Fool has made investing fun and easy for millions of people. Now, it custom designs its wit and wisdom for today's money-savvy teens. The Motley Fool Investment Guide for Teens helps teens stand out from the ho-hum mutual-fund crowd, build...