Have three different colored food trays, one color for vegan slop, one color foe Halal/Kosher slop, and a third for regular slop. Then the students can choose whichever slop they want.
Ahhh.... a solution. But that misses the point of the disks.
what if they decide to sin? what if they decide to have a taste of bacon?
The school might be sued for allowing the sin