Elementary Math Lessons: Triangles and Other Basic Shapes

When your child takes geometry in high school, he or she will go through several units on triangles and other shapes. Although elementary math lessons on shapes are not as in-depth as secondary geometry, your child will still learn the fundamentals he or she will need later on. Keep reading to find out what concepts will be covered in elementary math lessons about triangles and other shapes.

Find available tutors

What Elementary Children Learn about Basic Shapes

Shapes Learned in Elementary School

As early as kindergarten, children learn to recognize 2-dimensional shapes, such as triangles, squares, rectangles, circles and hexagons. Students are also introduced to 3-dimensional shapes, including cubes, spheres, cones and cylinders, in early elementary school.

Elementary students learn to divide shapes into equal parts, such as halves and fourths, and compare the different parts. For instance, if you divide a triangle in half horizontally, the top and bottom would not look the same; however, if you divide it in half vertically, the left and right sides would look the same. Eventually, students learn to identify this line as the line of symmetry.

Plane and Solid Shapes

Students recognize that closed, 2-dimensional shapes fall into the classification of plane geometry. All 2-dimensional shapes are called polygons. Solid geometry covers 3-dimensional shapes. The categories for shapes are based on the number of sides and angles they have.

Quadrilaterals have four sides and four angles. This category includes:

  • Squares
  • Rectangles
  • Trapezoids
  • Parallelograms
  • Rhombuses

Triangles have three sides and three angles. This category includes:

  • Right triangle
  • Acute triangle
  • Obtuse triangle

Shapes with more than four sides include the following:

  • Pentagon
  • Hexagon
  • Octagon

Perimeter and Area

In the elementary grades, students learn to find the perimeter of a polygon by adding up its sides. When given the perimeter and all sides but one, students can determine the length of the missing side. They will also be able to draw two rectangles that have the same perimeter but different areas, or conversely, two rectangles with the same area but different perimeters.

Third graders discover how to figure the area of a rectangle by deconstructing it into smaller, equal rectangles and counting them. They are then shown that multiplying the number of units in a row by the number of units in a column gives the same number as the area.

By the end of fifth grade, student have learned the formula for the area of a rectangle, A = l x w. They also know how to figure the volume of right rectangular prisms using the formulas V = l * w * h and V = b * h.

Did you find this useful? If so, please let others know!

Other Articles You May Be Interested In

  • More Blog Articles
    10 Top Math Apps for Elementary School Children

    Is your child struggling with math in elementary school? You may be able to get him or her excited about learning math by using an educational app on your iPad, iPhone, Android or other mobile device. Here are ten apps for elementary school children that may hold the key to math success.

  • More Blog Articles
    Elementary School Math Test Anxiety

    Too much anxiety about tests can be debilitating and result in poor performance. It can interfere with studying, cause difficulty with learning new material and even have a negative effective on a child's social interactions

We Found 7 Tutors You Might Be Interested In

Huntington Learning

  • What Huntington Learning offers:
  • Online and in-center tutoring
  • One on one tutoring
  • Every Huntington tutor is certified and trained extensively on the most effective teaching methods
In-Center and Online


  • What K12 offers:
  • Online tutoring
  • Has a strong and effective partnership with public and private schools
  • AdvancED-accredited corporation meeting the highest standards of educational management
Online Only

Kaplan Kids

  • What Kaplan Kids offers:
  • Online tutoring
  • Customized learning plans
  • Real-Time Progress Reports track your child's progress
Online Only


  • What Kumon offers:
  • In-center tutoring
  • Individualized programs for your child
  • Helps your child develop the skills and study habits needed to improve their academic performance
In-Center and Online

Sylvan Learning

  • What Sylvan Learning offers:
  • Online and in-center tutoring
  • Sylvan tutors are certified teachers who provide personalized instruction
  • Regular assessment and progress reports
In-Home, In-Center and Online

Tutor Doctor

  • What Tutor Doctor offers:
  • In-Home tutoring
  • One on one attention by the tutor
  • Develops personlized programs by working with your child's existing homework
In-Home Only


  • What TutorVista offers:
  • Online tutoring
  • Student works one-on-one with a professional tutor
  • Using the virtual whiteboard workspace to share problems, solutions and explanations
Online Only

Our Commitment to You

  • Free Help from Teachers

  • Free Learning Materials

  • Helping Disadvantaged Youth