What Does Common Core Math "Look Like"?

The Common Core math standards are very different from what we have been used to teaching in more traditional math programs. Another problem is that a number of commercial math programs are trying to cash in by labeling themselves as Common Core aligned without really providing instruction that follows the new guidelines. That's why I was pleased to find the Illustrative Mathematics website. It is a nonprofit online resource. This has some of the best Common Core math materials that I have come across. It lists both the practice standards and the grade level standards along with suggested lessons. Best of all, it gives clear examples of what proficiency on each standard should look like. It includes videos of students demonstrating what learners should be able to do to show mastery of each standard.