We cut out whole milk 2 years ago. Also we no longer let the kids that do not drink their milk be "saved" for someone else that wants one because the milk needs to stay under 41 degrees and if it is just sitting on a table or even with some ice it will not stay cold enough.
Just wondering how long your lunch time is? Around here I know that lunch isn't nearly long enough that the milk isn't sitting out nearly long enough for the minimal drop in temperature to affect it.
Kimya
Each class at our school gets only 15 minutes to eat and as soon as you're done you go to recess, they really eat fast! I wasn't aware that schools were selling whole milk anymore, ours hasn't for years.