Article starts with: "How well does Khan Academy teach? By Valerie Strauss", then "By Christopher Danielson and Michael Paul Goldenberg" on top of their contribution. At the end of the article there is a : "By Valerie Strauss". So attribution is displayed twice before text blocks and once after text blocks, if you don't see the failure in that, I am so sorry. I don't know how pedantic it is to confuse voices when they are attributed in two different ways when it is clear that the second way is the most common, but I will leave it to you to quantify it, not that I care for it. But do keep up the winding, you will be on to something, sometime soon.

Second: "Comparing decimals. Decimal fractions (decimals for short — the numbers to the right of the decimal point) are a notoriously challenging topic in the elementary math curriculum."

For the last time, decimals are NOT the numbers to the right of the decimal point like stated. "decimals" is being used for a subpar abbreviation of decimal fractions AND the left side numbers to the decimal point are a part of it, unlike what said authors state. Someone with pedagogical concerns should be awake when stating stuff like this and if you don't see the mess that is, that is your own problem. I have stated this already.