What happened? High-calorie beverages have lost their place in school vending machines. In a landmark agreement between major beverage distributors and the Alliance for a Healthier Generation — a joint initiative of the American Heart Association and the William J. Clinton Foundation — nearly all sales of soda to schools will stop.

Under the new guidelines, only lower calorie and nutritious beverages will be sold to schools. Cadbury Schweppes, Coca-Cola and PepsiCo have agreed to sell only water, unsweetened juice, and flavored and unflavored low-fat and fat-free milk to elementary and middle schools. In addition to these beverages, diet sodas, diet and unsweetened teas, flavored water and low-calorie sports drinks will be sold to high schools. Whole milk and regular soda will not be offered to any schools.

The new guidelines shrink serving sizes as well — 8 ounces for elementary students, 10 ounces for middle school students, and 12 ounces for high school students.

Although the changes will take effect in some schools sooner than others, the companies who've agreed to follow the new guidelines will work to implement the changes at all schools in the United States by the 2009 to 2010 school year. Officials hope that other beverage companies will follow suit.

The shift to lower calorie, more nutritious beverages is expected to help curb rising rates of childhood obesity. Beverage sales at school events open to the public — such as concerts and sporting events — won't be affected.

What does this mean to you? The average teenager consumes an estimated 250 to 325 calories a day in soda. More nutritious beverage choices at school may save students hundreds of calories a day. Encourage your child to make healthy food and beverage choices part of an active lifestyle.