The Food Standards Agency issued the notices after inspecting schools, nurseries and after-school clubs across Scotland.
Conservative education spokeswoman Mary Scanlon, who drew attention to the figures, called for better standards. "It is simply shocking that thousands of children across Scotland have been served food from kitchens that have failed standard hygiene laws," she said. "Parents will be horrified to know their child may have been served a meal from a facility that inspectors saw fit to serve with an improvement notice."
The "improvement required" notices are given if inspectors think a premises has failed to live up to the terms of the food hygiene information scheme, run in partnership with local authorities. The number of notices rose from four in 2009 to five, 23 and then 28 by 2012. There were 23 last year.
A Scottish Government spokesman said: "All food businesses whether private or local-authority-owned must comply with the current food hygiene regulations. Local authorities are responsible for food law enforcement in this type of establishment."
SNP councillor Douglas Chapman, education spokesman for council umbrella organisation Cosla, said: "Any recommendations for improvement are taken very seriously as we have a strong ethos relating to our duty of care to every child."