In this Grade 4 Saxon Math lesson, students learn to identify and draw triangles, rectangles, squares, and circles, including the concept that a square is a special kind of rectangle and that an equilateral triangle has three equal sides. Students also explore circle geometry, learning how to use a compass to draw circles and understanding key terms such as radius, diameter, and circumference. The lesson includes hands-on practice measuring and drawing shapes using a ruler and compass.
Section 1
📘 Triangles, Rectangles, Squares, and Circles
A circle is a closed, curved shape in which all points on the shape are the same distance from the center.
Next, you’ll practice drawing these basic shapes and explore their key properties, such as radius and diameter.
Section 2
A Square is a Special Kind of Rectangle
A square is a special kind of rectangle.
Think of 'rectangle' as a club with two rules: you must have four sides and four square corners. A square follows both rules perfectly, but it has one extra, VIP rule: all its sides must be the same length. So, every square gets into the rectangle club, but not every rectangle is special enough to be a square!
Section 3
Radius and Diameter
The radius of a circle is the distance from the center to the edge. The diameter is the distance across the circle through the center. The diameter of a circle equals two radii.
Imagine a pizza! The radius is the length from the exact center to the yummy crust. The diameter is a straight cut all the way across the pizza that passes through the center point. Since that cut is made of one radius going from the center to the left and another to the right, the diameter is always twice as long!
Section 4
Circumference
The circumference of a circle is the distance around—or the perimeter of—a circle.
Circumference is just the fancy, official name for a circle's perimeter. Imagine you could unpeel the edge of a cookie and lay it out in a straight line. The length of that line is the circumference! It’s the total distance an ant would have to walk to complete one full lap around the edge of the cookie.
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Section 1
📘 Triangles, Rectangles, Squares, and Circles
A circle is a closed, curved shape in which all points on the shape are the same distance from the center.
Next, you’ll practice drawing these basic shapes and explore their key properties, such as radius and diameter.
Section 2
A Square is a Special Kind of Rectangle
A square is a special kind of rectangle.
Think of 'rectangle' as a club with two rules: you must have four sides and four square corners. A square follows both rules perfectly, but it has one extra, VIP rule: all its sides must be the same length. So, every square gets into the rectangle club, but not every rectangle is special enough to be a square!
Section 3
Radius and Diameter
The radius of a circle is the distance from the center to the edge. The diameter is the distance across the circle through the center. The diameter of a circle equals two radii.
Imagine a pizza! The radius is the length from the exact center to the yummy crust. The diameter is a straight cut all the way across the pizza that passes through the center point. Since that cut is made of one radius going from the center to the left and another to the right, the diameter is always twice as long!
Section 4
Circumference
The circumference of a circle is the distance around—or the perimeter of—a circle.
Circumference is just the fancy, official name for a circle's perimeter. Imagine you could unpeel the edge of a cookie and lay it out in a straight line. The length of that line is the circumference! It’s the total distance an ant would have to walk to complete one full lap around the edge of the cookie.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter