Like most things, there's nothing wrong with alcohol - under the right conditions. Adults who can drink responsibly can enjoy alcohol without serious consequences. They do not, however, endanger their lives or the lives of others by getting behind a steering wheel after they've had too much alcohol to drive safely. For a teen, seeing people that they trust and care for having an occasional drink sends a mixed message. Unlike drugs that are illegal, alcohol is everywhere.
Teens are under pressure to experiment with alcohol.
It may be necessary to make a choice that is different from the choices of others. All 50 states have laws against driving under the influence of alcohol, with various penalties. It's not to soon to talk to your student about responsibilities that go with drinking alcohol. At this age, they may be riding with young inexperienced drivers. Also discuss the consequences and hardships of drunken driving.