20160514 TAKE AND GIVE:

Sorry, another big scare.

The British edition of Huffington Post reported an Internet sensation. I feel free to quote because the article mostly quotes the sources. Here it is, complete with the headline.

Year 2 SATs: Maths Question Aimed At Six And Seven-Year-Olds Is Completely Stumping Parents

Parents are claiming it’s too hard for their kids.

Parents are puzzled over a maths question that is aimed at Year 2 pupils taking their SATs exams.

Mum Louise Bloxham tweeted a photo of the task that involved working out how many people were on a train.

The question states: “There were some people on a train. 19 people get off the train at the first stop. 17 people get on the train.

“Now there are 63 people on the train. How many people were on the train to begin with?”

I gave the problem to TLG. In the middle of her 7th year, she is not a British 2nd year student of math, she is an American kindergartener learning to count to 20. Immediately, she started subtracting 17 from 63. Then she added 19. She messed up the computations - OK, there were the reasons for this - but her thinking was correct.

The parents' tweets quoted by HuffPost drew a familiar picture. In the age of free mandatory education, the majority of citizen perceive learning as a punishment. They hate school, then math, then - and most of all - algebra. How dare they ask our kiddies an algebra question?

No doubt, school is reaping what it sow, and it could not care less. Mandatory (or, more correctly, compulsory) education is a monopoly run on artificial sweeteners and fear.

Yet there is a math lesson in this story. Everybody assumed that the problem required equation, and equation is much-loathed algebra.

I had mentioned several times in this blog that I do not teach TLG equations. She simply knows how to solve them because she learned the operations of increment and decrement using X-bag.

Unlike addition and subtraction, increment and decrement are reversible, and not only conceptually so. I taught TLG the fully reversible algorithm of addition of shnumbers, on which she built her numerical carrying and borrowing skills.

Once TLG had gotten the problem, she started reversing the operations. This understanding was woven into the fabric of her mental arithmetic.

Increment and decrement are very useful for teaching. I will invoke them again and again.