That's a huge wave. If you've ever carried a gallon of water you might have a better appreciation for what it feels like to have tens of thousands of gallons of water smashing into you.
I have surfed, badly, and on waves that were maybe two feet high. I grew up in San Diego and am a strong swimmer so I thought - before I ever tried surfing - that it would be easy. It's not, and when you bury the nose of that board in a two foot wave and flip foot over head, it hurts. When you add a child to a classroom, you're adding the whole range of needs that child brings. It's like adding a foot to a wave - it's not just one foot of water, it's a foot of water that's 300 meters long. That's a lot of weight added to that wave.
Some people - people who have never taught 32 children - think it's not a big deal to add a child or two to a classroom. It is a big deal, and I would argue that just like surfing isn't about being a swimmer, teaching more children isn't a matter of being a teacher - it's an entirely different game, and not one that someone who wants what's best for children would support.