The Cake Method...No, I'm not talking about baking

I was in a 6th grade classroom the other day where the teacher had asked the students to find the GCF and LCM of 12 and 24. I peered over students’ shoulders, expecting to see lists of factors of each number or perhaps a prime factorization tree. Instead I saw this: Huh, must be a new way of factoring, I thought. Setting aside my concern that nobody in the class of eighteen recognized right away…