Mr. L’s Math

Pentominoes are wonderful creatures. They are fun to create, they can be colored by students, and there are a multitude of questions that can be posed, and many activities to pursue to stimulate and strengthen students’ minds.
This activity asks students to use a single pentomino to tessellate the plane. In other words, can you [...]

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Yesterday’s post talked about polyominoes; pentominoes, using 5 squares, are the polyomino that has gotten the most popularity due to their versatility in generating puzzles. Martin Gardner popularized them in 1957 in his math column in Scientific American magazine.
Pentomino puzzle pieces are simple to make; using card stock (or an old manila folder), create pentomino [...]

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Polyominoes: Puzzles, Patterns, Problems, and Packings, by Solomon Golomb is the definitive book on the subject by its creator who brought these wonderful objects to the mathematical world in 1953. Polyominoes are formed by groups of squares joined along their edges. Single squares are called monominoes. Two squares form the familiar dominoes. Then we have, [...]

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Sudoku is popular among math teachers since the puzzle requires only logic to solve, and logic/math reasoning is part of any mathematics class, often appearing in state standards. Most of the sudoku puzzles appearing in newspapers, like crossword puzzles, are of the 9×9 variety. These are normally too large for teachers to use when introducing [...]

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Adobe Acrobat Reader is the software of choice for documents that I make available for download at Mr. L’s Math since it’s a universal web standard. What follows is the “quick & dirty” guide to getting the most out of the files available for download at mrlsmath.com.
1. Adobe pdf files look exactly like original documents [...]

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Students will be so amazed at the patterns they find in the hundreds chart they will think you are a “mathemagician“. Once hooked, they will use algebra to understand the magic.
A favorite activity of my partner, Brad Fulton, and mine whenever asked to do a workshop for teachers, this chart can be found in [...]

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Most students are familiar with the “dirt equation“: D = R x T. But applying this simple equation to a nontraditional problem leaves most kids (and adults) wondering what happened.
Take the case of average speed - if you take a round trip going in one direction at 20 m.p.h. and returning at 30 m.p.h., the [...]

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cardioid-from-wikimedia-commons

Cardioids (heart shapes) are made by tracing a point on a moving circle that rolls without slipping on the outside of a circle of equal size. That’s quite a mouthful, but the graphic at the beginning of this post gives some idea of what this description is talking about.
You can also explore some nice sites [...]

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This activity is so easy to teach you might feel guilty for taking a
paycheck! Students will quickly pick up on the meaning and use of variables and will be able to substitute values into formulas to solve them. As a bonus, students can learn the Distributive, Associative, and Commutative properties as well!
My writing partner, Brad [...]

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For Firefox users: enjoy the java app; this apparently does not work with Internet Explorer - see below.
Sudoku has become an extremely popular puzzle in the last few years, especially among math folks. I’ve introduced the puzzle to my students using small 4×4 and 6×6 grids that can be solved in a few minutes so [...]

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