# Math

### The Problem of Anwar’s Camels

I just started reading Fractions in Realistic Mathematics Education by Leen Streefland, and there, on page 5, Streefland gives as an example an old puzzle problem that I remember giving my students more than 40 years ago. “An old Arab, Anwar his name, decreed before he died that his eldest son inherit one-half, his second… Continue Reading

### The Forty-Yard-Line is Opposite the Forty-Yard-Line?

One of the Common Core Standards for Mathematical Practice includes a focus on students knowing and using correct mathematical language and using clear definitions in discussions with others. There are times when everyday words are used in special ways in school mathematics, and it is important that students come to understand the precise mathematical meaning… Continue Reading

### How to Make Your Own O’Beirne’s Puzzle

Last week I showed you the O’Beirne puzzle and 30 of you very quickly responded to the offer of a free puzzle. I hope you’ve gotten it by now. In future posts I’ll explore with you some ways to use the puzzle to engage students with Common Core Standards for Mathematical Practice as well as… Continue Reading

### Do We Really Understand What Math Is?

What would you or your students say math is? Some common answers could be numbers, addition, subtraction . . . Below are the posters a group of AIMS trainers created answering that question. Most people don’t understand what math really is. If you have read some of my previous posts, you know my elementary and… Continue Reading

### Further Explorations with O’Beirne’s Cube

This post is a quick follow-up to the one from last Monday in which I showed you the O’Beirne cube puzzle. After we finished filming for that post, we still had the six puzzles on the table and we got to talking about the sequence in which the puzzle comes apart and goes back together… Continue Reading

### How to Equip Your Students to Better Understand Multiplication, Part Three

I never liked word problems as a student. It was difficult for me to figure out which procedure to use, but I really didn’t like problems like this: Robert is three times as old as his younger brother Mark. Mark is 7 years old. How old is Robert? As I reflect on my experience, I… Continue Reading

### O’Beirne’s Cube

This post is a bit of an experiment. First of all, I want to tell you about and show you a put-together-puzzle called O’Beirne’s cube. This is not just any puzzle. It is one of the most amazing, delightful, and elegant puzzles ever invented. There are people who know about things like this who rank… Continue Reading

### How to Equip Your Students to Better Understand Multiplication, Part Two

Using arrays has become much more prominent in the classroom. At first glance arrays seem very straightforward and simple for students. But what are the connections that are essential for students to build understanding of the concept of multiplication through arrays? Arrays are a model of multiplication. Just because your students can build an array… Continue Reading

### Friday Institute: A Common Core Resource

I want to share with you two very helpful, quite extensive Common Core Math resources that are available from the Friday Institute for Educational Innovation at North Carolina State University. The first resource is an interactive map of all of the Common Core Content Standards organized into 18 learning trajectories or progressions http://www.turnonccmath.net/index.php?p=map. For example,… Continue Reading

### How to Equip Your Students to Better Understand Multiplication, Part One

As I have coached and taught in the classroom, the three most popular ways to describe multiplication is showing ______ groups of ______, using repeated addition and making arrays. Now all of these methods have their place in a student’s understanding of multiplication, but if these methods are all they know, their understanding is limited.… Continue Reading