6th Grade Geometry Lessons and Teaching Strategies

Guide for Teaching Geometry to 6th Graders

What to Cover

Although each state has its own curriculum standards and learning goals, in 6th grade geometry, students will:

1. Compose and decompose triangles, certain quadrilaterals and other polygons into other shapes.
2. Finding the volume of a right rectangular prism using the formulas V = lwh and V = bh.
3. When given coordinates for the vertices, students use a coordinate plane to draw polygons, find length of a side that joins points with the same first or second coordinate.
4. Use nets composed of triangles and rectangles to symbolize 3-dimensional figures and to determine the figures' surface areas.

Teaching Strategies

Your 6th graders need to learn certain facts and procedures to meet those goals. Strategies for teach each goal are provided below.

Area of a Triangle

Graph paper or geoboards can help 6th graders visualize how to break shapes apart. For instance, to find the area of a right triangle, you can divide the area of a rectangle by two.

Continue practicing by dividing other triangles into two right triangles. Find the areas for each right triangle and add them together. Then, take the same triangle and use the formula A = ½(b)(h) to show that this gives the same answer. For other geometric shapes, divide (decompose) them into triangles and rectangles to compute the area.

Unit Cubes

Sixth graders have already learned to determine the area of a rectangle using cubes that equal one. By using cubes that are smaller than one (e.g., ½ of a unit), they begin applying their knowledge of fractions to determine the area of a rectangle.

Coordinates

Students can enjoy working with coordinates by exploring dot-to-dot pictures on a graph, where the dots are placed using coordinates. They can then go on to determine the areas of either a whole picture or just certain portions of a complex picture.

Nets

Give students a net and guide them in making the polyhedron from it. Alternatively, provide the students with a polyhedron and ask them to draw a net for it. Either way, students will learn to find the triangles and rectangles that form the polyhedron and find the area of each. By adding them together, they'll discover the surface area of the shape.