Funny comment: “Hundred bucks says that method of teaching multiplication was infinitely more effective than Common Core.”
To compare the traditional teach methods of the 1910’s to Common Core you would have to divide the successes of the 1910’s by the successes of Common Core.
So considering that Common Core is totally ineffective or put it mathematically zero percent effective and the teaching methods of the 1910’gave us the birth of quantum mechanics and the electrical grid so you would put the value of those methods at a sizably large number.
Therefore having the effectiveness of 1910’s methods valued at a large number divided by Common Core methods valued at zero we must say that effectiveness of Common Core methods are “undefined”.