## 2+2= deep learning

In The School of Deep Understanding, Diana Senechal satirizes the gee-whiz discovery of “deep learning” in Common Core math classrooms.

The teacher, Gideon Pelous, buzzed about the room like a shimmering dragonfly while the children—second-graders from the deep inner city—discussed the essence of numerals in small groups.

Before the Core, students would be taught that two plus two equals four, but they would never know why.

“I just had a realization,” said Shelly Thomas, arranging four rectangular blocks in front of her. “I used to think that numerals were quantities. I was trying to figure out what the curve on the 2 meant, and what the double curve on the 3 meant. I even tried measuring them with my ruler. Then I had the insight that numerals aren’t quantities, but rather symbols that represent quantities.”

“You mean to say—“ sputtered Enrique Alarcón as he seized a crayon.

“Yep,” she continued. “This 1 here represents a unit of something. It can be a unit of anything. Now, when we say ‘unit,’ we have to be careful. That’s another thought that came to me, but I haven’t figured it–.”

“I have,” interrupted Stephanie Zill, banging on her Curious George lunchbox. “We use the word ‘unit’ in both a contextual and an absolute sense. That is, a unit is unchanging within the context of a problem, but it may change from problem to problem. Also, certain defined units, such as minutes and yards, have a predefined size that doesn’t change from one context to the next—until you consider relativity, that is.”

“Oh, I get it,” said Enrique. “So, this numeral 1 represents one unit, which could be a unit of anything, but within a given problem, the word “unit” does not change referent unless we are dealing with more than one kind of unit at once. Hey, what color crayon should we use: magenta or seaweed?”

“Magenta,” said Shelly.

Stephanie and Orlando go on to discuss the “sockiness” of socks to conclude that two pairs of socks equal four socks in the real world.

## ‘Deep learning’

Teachers are looking for ways to engage students in “deep learning,” reports John Tulenko on PBS.

At King Middle School in Portland, Maine, science teacher Peter Hill’s eighth graders started a four-month study of energy  by building robots. They’ll finish by designing an energy device that could help people somewhere in the world.