How would you answer this 1st grade test question. Explain your reasoning.

[HereSince1628]

78. I have a question about this...is it really better for most students

trying to learn basic arithmetic this way? I don't actually know.

I don't challenge that it works. It does.

It seems it's a way of doing subtraction without the concept of "borrowing" a unit from the next larger order to the left. But it still seems as though it requires memorizing all the differences possible between 0 an 10.

I'm fairly sure no one setting up a spreadsheet or entering values into a calculator would do math that way. So I'm not sure what this approach foreshadows that benefits later computational skills.

For a person like me who in learning arithmetic had to also learn to be very careful about misperceiving written 3's, 5's, and 8's as the same number every step represents a risk for a mistake. So, I'm not fond of things that add steps.

I do get that the structure of presentation during early learning has a very long lasting effect.

55 years ago when I was learning numbers and basic arithmetic Miss Elledge presented numbers 1 through 12 as upward steps on a cartoon staircase...later numbers greater than 10 were presented as columns of 20's, 30's, 40's, etc. I've never been free of that visual and if asked to rate something on a scale from 1 to 10 I visualize it as a position on that staircase. I'm not sure that did me much good with thinking in terms of number lines or coordinate planes. Things which are necessary if you are going to solve a system of equations for a dominant eigenvalue.

If this is really a better system for learning foundational skills that facilitate learning advanced math practice I'd be good with that.