@rebeccawatson
On meats. Mix up the types, and always fully cook.
A study that had bad permissions and thus was retracted, showed that schools that fed kids meat for high quality protein instead of vegetable protein, did about 10 IQ points better on IQ tests.
More recently a country in Africa decided to provide meat to some schools for their lunch soup. In those schools kids learned more, and were better behaved. That study should still be able to be found.