Why is maths education a huge political issue in America?
The latest viral video purporting to show the complexity of America's Common Core standards shows why education is an issue in a key election year.
How would you teach a child to solve a maths problem like 43-13?
One easy way probably springs to mind - put the second number below the first and work in columns. But that's not the only way to solve a subtraction problem. And millions of American children are being taught alternative methods under a programme called Common Core, which seems to have achieved the impossible - it has made mathematics education a hot political issue.
At its heart, Common Core is a set of grade-level standards in maths and English designed to give some uniformity to America's patchwork of state and local education systems. But it also involves teaching methods that emphasise understanding alongside rote learning. That's where the alternative subtraction methods come in - and that's also where critics of Common Core say it makes subjects too difficult and complicated.
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That critique was encapsulated by a phenomenally popular video posted by an Ohio woman, Melissa Strzala. In the video, which has been watched more than 17 million times, Strzala solves 43-13 the traditional way, and then lays out what she says is a Common Core-endorsed (much longer and more complicated) method.
The video generated tens of thousands of comments, many of which took issue with Strzala's characterisation.
"This is not Common Core," read one comment. "This is someone's attempt to mislead those who don't know so that their agenda can be promoted."
Others criticised Common Core and education officials who adopted the system.
"This makes me want to home school my children!!" one commented.
Strzala is a conservative and a determined opponent of Common Core - her latest video was one of several she's made on the subject. She declined a BBC Trending interview request. But her social media activism, and the comments of those who have responded to it, demonstrate how something that was meant to raise educational standards - a seemingly universal goal - has become a hot political topic in America.
Common Core was adopted in most US states starting in 2009, and although it was developed by both Democratic and Republican administrations (former Florida Republican governor Jeb Bush was a fan) the timing of its implementation has linked it, in conservative circles at least, to President Obama.
All of the main Republican candidates have come out against Common Core, with Donald Trump perhaps the most vociferous opponent, calling it a "disaster."
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Experts who are in favour of Common Core say much of the opposition comes from parents who don't understand why their children are being taught differently from how they were taught in school. BBC Trending has previously reported on how comedian Louis CK tweeted pictures of his daughter's Common Core based homework because neither she nor he could get to grips with the new system.
"I think it's blown up largely because parents … don't understand these new approaches and see them as unnecessarily complicated for certain problems," says Morgan Polikoff, a professor of education at the University of Southern California. "But in fact these are working to help students develop a conceptual understanding of what subtraction actually is - so when they are confronted with subtraction problems in real life they have a way to choose the most appropriate approach to whatever problem is in front of them."
But there are experts on the other side of the debate. Stanford University mathematics professor James Milgram sat on a Common Core committee and has studied education around the world. He's not against common standards but says the focus of maths education should be on simple ways to learn.
"The way kids learn and the way mathematics has been classically taught - and is taught in the high achieving countries - is that students learn one method."
Reporting by Anisa Subedar
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