9-12
Instead of considering the diagonals within a quadrilateral, this lesson provides a unique opportunity: students start with the diagonals and deduce the type of quadrilateral that surrounds them. Using an applet, students explore certain characteristics of diagonals and the quadrilaterals that are associated with them.
9-12
This lesson is based on the Triangle Classification problem, in which students attempt to classify the triangles formed in a plane when a randomly selected point is connected to the endpoints of a given line segment.
6-8
Students explore the Fibonacci sequence, examine how the ratio of two consecutive Fibonacci numbers creates the Golden Ratio, and identify real-life examples of the Golden Ratio.
3-5
People come in all different sizes and can be measured in lots of different ways. In this lesson, students can make their own fascinating discoveries and become aware of the concepts of ratio and proportion as they relate to measuring features of their own bodies.
9-12
Students begin with a problem in a real-world context to motivate the need to construct circumcenters and then incenters of triangles and to make sense of these constructions in terms of bisecting sides and angles.
6-8
A real-life example—taken from a bagel shop, of all places—is used to get students to think about solving a problem symbolically. Students must decipher a series of equations and interpret results to understand the point that the bagel shop’s owner is trying to make.
9-12
In this lesson, students will examine numeric, algebraic, and graphical representations of compositions of function in the context of successive discounts at a retail store.
9-12
Given growth charts for the heights of girls and boys, students will use slope to approximate rates of change in the height of boys and girls at different ages. Students will use these approximations to plot graphs of the rate of change of height vs. age for boys and girls.
9-12
Students will collect information about the National debt, plot the data by decade, and determine whether an exponential curve is a good fit for the data. Then student groups will determine and compare common traits and differences in changes in the National debt in three major eras: the Civil War, World War I, and World War II.
6-8, 9-12
Students will be introduced to modular arithmetic by first examining a five-hour analog clock and its mathematical properties. Then students will investigate patterns and relationships that exist in 12-hour addition and multiplication clock tables.
