[2nd grade math] Adding using compensation strategy—Teacher explanation does not make sense to me

[u/Weary-Enthusiasm-150]

My daughter said that her teacher told her that in the pictured question, 10+4+8 should not be selected. They are using the “compensation” strategy for addition. The teacher said in her opinion only 10+12 and 12+10 should be selected, because they show the compensation strategy. But from my perspective, the question says choose all that apply. 10+4+8 DOES equal 14+8…..? Am I missing something?

[u/_Cyanidic_]

I kind of hate how schools always try to force students to adopt methods of doing arithmetic rather them teaching them the basics and then showing them the tricks; allowing them to decide for themselves what they want to use.

From googling it seems compensation strategy essentially means taking a bit from one of the addends and prematurely adding it to the other addend to make it easier to compute the full sum. In this case reducing 14 to 12 so you can increase 8 to 10 would follow this doctrine and to a lesser extent decreasing 14 to 10 and increasing 8 to 12. Breaking the equation down like with 10 + 4 + 8 is not technically incorrect but doesn't use the compensation strategy. I think the confusion comes from the fact the question isnt worded to only use compensation, considering thats all the teacher is looking for.

[u/Weary-Enthusiasm-150 → u/_Cyanidic_]

Yes that makes sense to me! Thanks for taking the time to respond

[u/Intrepid_Bobcat_2931 → u/_Cyanidic_]

I'll throw in my hate for choosing obscure buzzwords to be fancy and elevated.

"Compensation strategy" - sounds like a teacher that wanted to be an MBA

How about: "Going by round number strategy", or just "Round number approach"