The mum of eight was apparently mortified and I don't blame her.
While we all need to encourage healthy eating habits in our kids, when did kindy teachers become food Nazis? Do they have degrees in nutrition? And what right does anyone have to tell a parent what they can feed their child?
It's time for these self-appointed lunchbox loons to back off. Most parents are doing the best they can and a piece of cake is hardly a problem if there's other healthy options in the child's lunchbox.
I'm all for education and steering parents in the right direction and South Australia's RightBite programme, which classifies foods into red, amber and green categories, is a great initiative to help parents make good choices.
But a personalised note? With an infantile frowning face? It's like putting a big red cross on a parent's forehead.
Sure, make suggestions through the newsletter and educate kids themselves to make healthy choices because ultimately they'll be in charge of their own diet and exercise.
But lunchbox shaming busy parents is out of line. Teachers and parents should be working together - not sending filthy passive aggressive notes.
Besides, who's to know the cake wasn't made with beetroot!
Angela Mollard is New Idea's Parenting Editor