There will be chips just twice a week, and fizzy drinks will be replaced by water or milk.
And chocolate won't be on sale.
Beating the flab
The rules are part of a plan by Scottish politicians to help kids slim down.
It should help you do better in lessons, too.
Also in the rules, you can expect:
- two portions of fruit and veg a day
- pasta or rice once a week
- bread every day
- garlic bread only twice a week
Schools are being given time and extra money to get ready for the changes.
Primary and special schools should be following the new rules by December
2004, and secondary schools by December 2006.