Factors, Multiples and Primes
14 Divisors Stage: 3 Challenge Level: What is the smallest number with exactly 14 divisors? Dozens Do you know a quick way to check if a number is a multiple of two? How about three, four or six?
Webcast - Beyond Slices of Pizza: Teaching Fractions Effectively
This webcast, Beyond Slices of Pizza: Teaching Fractions Effectively, was coordinated by The Center on September 23, 2008. Video from the webcast Complete video from the webcast. (no longer available)Additional video interview with Denise Mewborn: Fractions are everywhere in the real world (no longer available)

illustrativemathematics
Illustrated Standards Count to 100 by ones and by tens. (see illustrations) Count forward beginning from a given number within the known sequence (instead of having to begin at 1).
NRICH enriching mathematics
Teachers Primary Pupils Secondary Students
NYC Math
Keywords (optional) Enter keywords (e.g., K.OA.3, informational text, arguments, quadratic equations, etc.) Grade (select at least one) Subject (select one)
MathVIDS! Home
Welcome to MathVIDS! A Resource for Teaching Mathematics to Struggling Learners MathVIDS is an interactive website for teachers who are teaching mathematics to struggling learners made possible through funding by the Virginia Department of Education.

The University of Arizona - Institute for Mathematics & Education
The Common Core State Standards in mathematics were built on progressions: narrative documents describing the progression of a topic across a number of grade levels, informed both by research on children's cognitive development and by the logical structure of mathematics. These documents were spliced together and then sliced into grade level standards. From that point on the work focused on refining and revising the grade level standards.
Common Core State Standards for Mathematics
Math Playground's games are aligned to Common Core Math Standards.New Common Core videos for grades 1-3. advertisement Common Core Math Games and Problem Solving Activities Common Core Videos for Grades 1 to 3 Place Value

Standards for Mathematical Practice
"Does this make sense?" Mathematically proficient students start by explaining to themselves the meaning of a problem and looking for entry points to its solution. They analyze givens, constraints, relationships, and goals. They make conjectures about the form and meaning of the solution and plan a solution pathway rather than simply jumping into a solution attempt. They consider analogous problems, and try special cases and simpler forms of the original problem in order to gain insight into its solution.

The Math Forum @ Drexel University
The Math Forum has a rich history as an online hub for the mathematics education community. A debt of gratitude is owed to the dedicated staff who created and maintained the top math education content and community forums that made up the Math Forum since its inception. NCTM will continue to make many of the most popular parts of the Math Forum content accessible to the mathematics education community. We hope that you will join or continue to be a member of the NCTM community to access even more high-quality resources for teaching and the learning of each and every student. Problems of the Week