After this report, officials are worried the massive amount of time, effort and money that's gone into transforming school food over the past five years will be wasted.
The research was carried out for the School Food Trust.
Knives and forks
Children eating school dinners
The trust carried out experiments in some primary and secondary school canteens across England, to see what would make them better for children.
They found that even little improvements can help, such as giving pupils more time to eat their lunch, and giving them proper knives and forks instead of plastic ones.
Deputy head teacher Jane Nicholls, from Langley Park Girls School in London, is keen on this approach. Some of the experiments were carried out at her school.
"The small changes we made to the dining room made a huge difference to our pupils and turned lunch into a special occasion where the girls took the time to sit down and really appreciate their food," she said.