Return to Mathematics IndexGeometry and the Geoboard

Jacqueline Darling Simmye Anderson Community Academy

6315 S. Claremont Avenue

Chicago IL 60625

312-535-9070Objective(s):

The 6th grade student will be able to:

1. Discover the fun of using the geoboards as they learn many mathematical

concepts.

2. Visualize the concepts of squares, rectangles, triangles and polygons.

3. Explore line segments, areas, and perimeters.

4. Demonstrate the phenomenological approach in learning geometry.

5. Understand the multicultural aspect of geometry and the geoboard.Materials:

Geoboard

Geobands

Dot paper

Overhead projector (optional)

Activity sheets

Strategy:

Discuss with the students the origin and the various types of geoboards

(square and circle). Issue the geoboards and the geobands to each student.

Let the students explore different shapes on their own. Elicit from the

student ways the geoboard can be used to explore different geometric

shapes.

Introduce dot paper to the students. Use the overhead projector to show the

relationship between the geoboard and the dot paper.

Explain the coordinates on the geoboard and let the students find points.

Show what one square unit is on the geoboard.

Give example of a line segment on the geoboard. Let the students practice

making line segments, horizontally, vertically, diagonally, and shortest to

the longest.

Activity 1.

Locate the circled points on your geoboard. Name them. (On the overhead

projector select points to circle.)

Activity 2.

The game Tic Tac Toe is an appealing way to introduce a coordinate system

for graphing. Start with a five by five array of dots on the chalkboard.

The plastic geoboard for the over-head projector works well for this

activity.

Ask a student to name two numbers. Ask another student to name two

numbers. Mark one team's points with X's and the other teams's with O's.

Three in a row wins. Teams take turns giving you pairs of numbers. If a

pair is given that does not fit on the graph, that turn is lost. If a

pair is called and that dot has already been marked, that turn is lost.

After playing this game a few times, change the rules so that it takes

four in a row to win.

Activity 3.

Make the figures shown on the overhead projector on your geoboard.

(Display and label various polygons A, B, C, etc. and let A have

an area of 6 square units). Copy on dot paper.

Activity 4.

Using the activity sheets you made in Activity 3, find the areas of the

polygons.

The geoboard is not needed for this activity.

Count the squares in example (a). How many do you see? The number

of squares in the figure is called the area of the figure. The

area of the figure in example (a) is 6. Notice we have put the

6 inside the figure. Write the correct area inside of each of

the other figures.Performance Assessment:

In the previous activity you were to make different figures on your geoboard

with different areas. Now, see how many figures you can make on your

geoboard, all of which have an area ofsixsquare units. This larger number

allows much more variety. Be sure to check the area on your geoboard and

sketch it. Remember, by different we mean different size and shapes. (You

will need to distribute dot paper.)

Conclusions:

Geoboards enable us to count units of area of geometric figures.

References:

Meserve, Bruce E., Sobel, Max A., Dorsey, John A.,Contemporary Mathematics,

4th. Edition, Prentice Hall, 1987.

Cech, Joseph P. and Tate, Joseph B.,Geo-board Activity Sheets, Ideal School

Supply Co. , Oak Lawn, Il. 60453, 1989.