Illustrative Mathematics
The Lighthouse Problem
Long considered the symbol of safe harbor and steadfast waiting, the lighthouse gets a mathematical treatment. The straightforward question of distance to the horizon is carefully presented, followed by a look into the...
Illustrative Mathematics
Coins in a Circular Pattern
What starts as a basic question of division and remainders quickly turns abstract in this question of related ratios and radii. The class works to surround a central coin with coins of the same and different values, then develops a...
Illustrative Mathematics
Accuracy of Carbon 14 Dating II
The scientific issue of carbon-14 dating and exponential decay gets a statistics-based treatment in this problem. The class starts with a basic investigation of carbon content, but then branches out to questions of accuracy and...
Illustrative Mathematics
Seven Circles III
A basic set-up leads to a surprisingly complex analysis in this variation on the question of surrounding a central circle with a ring of touching circles. Useful for putting trigonometric functions in a physical context, as well as...
Illustrative Mathematics
Two Wheels and a Belt
Geometry gets an engineering treatment in an exercise involving a belt wrapped around two wheels of different dimensions. Along with the wheels, this belt problem connects concepts of right triangles, tangent lines, arc length, and...
Illustrative Mathematics
Running Around a Track II
On your mark, get set, GO! The class sprints toward the conclusions in a race analysis activity. The staggered start of the 400-m foot race is taken apart in detail, and then learners step back and develop some overall race strategy...
Illustrative Mathematics
Eratosthenes and the Circumference of the Earth
The class gets to practice being a mathematician in ancient Greece, performing geometric application problems in the way of Eratosthenes. After following the steps of the great mathematicians, they then compare the (surprisingly...
Illustrative Mathematics
Similar Triangles
Proving triangles are similar is often an exercise in applying one of the many theorems young geometers memorize, like the AA similarity criteria. But proving that the criteria themselves are valid from basic principles is a great...
Curated OER
Math Games for Skills and Concepts
A 27-page packet full of math games and activities builds on algebra, measurement, geometry, fractional, and graphing skills. Young mathematicians participate in math games collaboratively, promoting teamwork and skills practice.
PBL Pathways
Medical Insurance 2
Make an informed decision when choosing a medical insurance provider. An engaging lesson asks your classes to write piecewise models to represent the cost of different medical plans. The project-based learning activity is a variation of...
Teach Engineering
Searching for Bigfoot and Others Like Him
Individuals create a GIS data layer in Google Earth that displays information about where one might find seven different cryptids. The class members research to find data on cryptid sightings they can include in their data...
PBL Pathways
Total Cost to Produce the Turbo Blender
Class members blend their knowledge of functions and problem-solving skills to provide business advice to the Turbo Blender manufacturers. Through a project-based approach, learners examine marginal cost data to produce a function....
Mr. Roughton
Pawn Stars: Africa
What element was worth more during the growth of empires in West Africa: gold or halite? After examining various pieces of evidence of primary and secondary source documents placed around the room, your class members will each make a...
TeachEngineering
Teach Engineering: Can You Resist This?
This lab demonstrates Ohm's law as students set up simple circuits each composed of a battery, lamp and resistor. Students calculate the current flowing through the circuits they create by solving linear equations. After solving for the...
TeachEngineering
Teach Engineering: You Are There, First Flight
Students learn about archives and primary sources as they research original historical documents. While preparing an imaginative first-person account as if witnessing an historical event, they learn to appreciate the value of the...