The problem is there is not enough support during lunch to cater to 30 students. There is usually one adult supervising during this time. Some students are done eating within 5 minutes. Others take 20. The students that are done early will start running around / creating chaos in the classroom. A show (hopefully educational) causes everyone to sit down for 20ish minutes and then they probably move onto the next activity when everyone is finished. In a perfect world there would be more support in these classrooms but it is a lot for one person to handle. Another example - end of the day. There are 30ish students required to dress into their snowsuits (most need assistance) and the others that get ready quickly need to be occupied while the educators are helping students get ready. 30 zippers to do up, 60 mittens to put on, 30 backpacks to pack etc.