6-8
Using a scheme similar to the one in the Rectangle
lesson of this unit, students will further explore the concepts of
identity, inverse, and commutative and associative properties. Students
investigate and analyze moves performed with a plus sign, and an online
activity is available to help students with this investigation.
3-5, 6-8
This lesson uses a real-world situation to help develop students' spatial visualization skills and geometric understanding. Emma, a new employee at a box factory, is supposed to make cube‑shaped jewelry boxes. Students help Emma determine how many different nets are possible and then analyze the resulting cubes.
6-8
In this lesson, students will compare the price of a toll to the distance traveled. Students will investigate data numerically and graphically to determine the per-mile charge, and they will predict the cost if a new tollbooth were added along the route.
6-8
Students will measure the length and width of a rectangle using both standard and non-standard units of measure. In addition to providing measurement practice, this lesson allows students to discover that the ratio of length to width of a rectangle is constant, in spite of the units. For many middle school students, this discovery is surprising.
6-8
Students measure the circumference and diameter of circular objects. They calculate the ratio of circumference to diameter for each object in an attempt to identify the value of pi and the circumference formula.
6-8
Using a circle that has been divided into congruent sectors, students will discover the area formula by using their knowledge of parallelograms. Students will then calculate the area of various flat circular objects that they have brought to school. Finally, students will investigate various strategies for estimating the area of circles.
9-12
Students measure the diameter and circumference of various circular
objects, plot the measurements on a graph, and relate the slope of the
line to π, the ratio of circumference to diameter.
3-5
A puzzle involving five dice and a non-standard pattern is used to promote problem-solving skills.
6-8
In this lesson, students develop the area formula for a triangle. Students find the area of rectangles and squares, and compare them to the areas of triangles derived from the original shape.
6-8
Students will use their knowledge of rectangles to discover the area formula for parallelograms.
