We should be teaching kids what it means to be healthy. But sending a 3-year-old home with a note shaming them (and their parents) for including a slice of chocolate cake in their school lunchbox? That’s too far. But it’s exactly what happened to one Australian family.

The note comes from a country-wide policy that uses the “traffic light system” to categorize food—green for good-for-you foods and red for the ones you want to avoid.

But that system is flawed. Preaching the idea that certain foods (cake, candy, or fried food, for example) are always evil can set kids up with unhealthy relationships to food. It’d be more helpful to teach moderation—chocolate cake is fine as an occasional treat—and stop teachers from judging a student’s overall eating habits based on one lunch.