system
Given the following post, respond as if you're commenting on Reddit:
human
CMV: the original method is better than common core maths.

Why was it changed? Who changed it? I really need someone to tell me what's so special about this new way of doing simple maths. I don't understand! Well... I do understand how it's done but I don't understand why it's better than the original method. I mean, if it isn't broken don't fix it am I right!? I know a lot of parents that are even more confused because they don't understand how this new maths is done therefore leaving them unable to help their children with maths that require them to show their work. Should they relearn mathematics? No! Because what they originally learned was not wrong, but I've heard too many stories about children getting low grades as a result of their parents helping them with their homework because they "did it wrong" even though they had the same answers just different work shown. 

Edit: my view has been changed. Thanks for all your comments.
gpt
common core is a curriculum, not a method.

One part of the common core curriculum that some people are upset with is teaching several means of computing addition and multiplication.

These means of computing addition are meant to convey the mathematical properties of addition, so that the student not only understands how to add numbers like 5 and 8 but understands the principles behind addition sufficiently to go into algebra with an intuition for how to apply their knowledge of addition to quadratic equations. 

people who learned mathematics as rote memorization will struggle to pick up new approaches that are meant to convey underlying principles, sometimes in part because those adults never learned the underlying principles (and relied on rote memorization of mnemonics like FOIL instead of an intuition for basic mathematical properties of addition and multiplication).  These underlying principles are important.  They do convey a deeper understanding that enables students to pick up later concepts faster and retain them better.