Common Core: Expert Guides and Resources

As a parent, you’re most likely to encounter the Common Core State Standards for Mathematics (Common Core Standards for short) in the homework that your child brings home. The Common Core Standards are a set of statements about what students should know and be able to do at each grade level from kindergarten through high school.

In Common Core math, first grade students need to begin thinking about the properties of numbers more deeply. One important property of all numbers is that they can be decomposed. When you decompose a number, it means that you take the number apart. You can do it in many ways; for example, you can think of 8 as 4 + 4, or as 3 + 5, or as 9 – 1, and so on.

If your child is in kindergarten, you can help them begin to compare and classify things. This will strengthen their ability in other important areas of Common Core math. Kindergarteners notice characteristics of things that can be measured. These characteristics are called measurable attributes. Measurable attributes of a person include height, favorite color, shoe size, and bedtime.

To learn Common Core geometry, a kindergarten student begins by studying shapes that she finds in her world. Nearly all children will come to school with ideas about what shapes look like and basic names for shapes. Kindergarteners spend time trying to describe shapes precisely. A student entering kindergarten may think of squares and rectangles as unrelated shapes.

Want to avoid raising a math‐o‐phobe? Here are five proven ways to help your child become successful in his or her Common Core math classes. Talk about math together Set yourself a goal to ask "how many?," "what shape?," "how do these compare?" and "how do you know?" at least once a day. Don't worry about asking a question that's too difficult; your child can take a guess, and then you can talk.

One unique aspect of the Common Core State Standards is that their focus goes beyond the familiar content of numbers, geometry, algebra, and statistics. They also include a set of Standards for Mathematical Practice, or SMP, that describe how people work when they're doing math. The SMP apply across all grade levels, with kindergarteners operating at a level of sophistication appropriate to them and high school students working at a much more sophisticated level.

In Common Core math, sixth graders apply their knowledge of factors and multiples to look for the greatest common factor (or GCF) of two numbers and the least common multiple (LCM) of two numbers. The greatest common factor of two numbers is the largest number that is a factor of both numbers. The first step in thinking about GCF is to think about common factors.

In math, there are many kinds of sameness. In Common Core geometry, eighth grade students study congruence and similarity as two ways of talking about how two shapes are the same. Two shapes are congruent if you can move one so that it perfectly matches the other one without stretching or deforming it. Two shapes are similar if you can do the same thing, except that you're allowed to stretch or shrink the shapes proportionally — you can double all the lengths on one of the shapes, for example.

Sixth grade is the first time that Common Core math students start to solve problems using variables and the property of equivalence (specifically, the distributive property). They typically use variables that closely match the values they represent, so s for side length, v for volume, and so on. They also notice that some expressions — even though they may look quite different — always have the same values as each other, and they explore this property, called equivalence.