These events tempt even those who have never had a drop of alcohol in their lives to give it a try, so the AAAS has urged parents to talk to their children about drinking, and cited the five reasons why alcohol can ruin prom night or graduation.

They May Not Remember Teens spend months preparing for prom and graduation and cherish those memories throughout their lives. But if they drink, there's a good chance they may not remember any of it.

The hippocampus, the area in the brain that stores memory, is still maturing in teens. Drinking even small amounts of alcohol can make kids forget what they did while drinking and even black-out completely.

They May Do Things They Don't Want to Do Alcohol helps release inhibitions, and teens who drink may indulge in risky behaviours such as unprotected sex or drunk driving.

The brain's prefrontal cortex, which is involved in planning and decision-making, does not completely mature until a person's mid-to-late twenties. Using alcohol can harm a teen's ability to reason and weigh options instead of just doing something because it is fun or feels good.

They May Get Into Fights Research shows that teens who drink are often more violent than those who do not. For example, 7th graders who drank averaged almost twice as many violent behaviours as those who didn't, according to a recent study by the Centres for Disease Control and Prevention.

A report from Ormond Street Hospital in London says that almost a fifth of 12-13 year olds and more than a quarter of 14-15 year olds reported damaging or destroying things after drinking.

They May Get Really Sick Who wants to spend prom night throwing up or so dizzy that he or she can't dance? Alcohol can irritate the stomach causing dehydration, which often leads to vomiting and dizziness. Throwing up also may be a sign of alcohol poisoning, which causes body systems to break down and requires immediate medical care. That's a good way to ruin everyone's night.

They May Feel Horrible for the Next Couple of Days Even small amounts of alcohol can cause a hangover, which can lead to thirst, dizziness and light-headedness.

Headaches caused by blood vessel expansion and sleepiness due to narcotic effects on the central nervous system are other symptoms of a hangover. Your teen may have to forgo events scheduled for the next day or two while trying to get better.

"A time of year that's supposed to be fun for parents and kids can turn ugly quickly," Shirley Malcom, head of Education and Human Resources at AAAS, said.