Perimeter and Area

              By F. West
Objectives
Students will understand the meaning of perimeter & area
and apply it in problems. GLEC Standards and Benchmarks
M.UN. 03.05 II .3.2
3 grade math
Learning Resources and Materials

Ruler
Graph paper
Methods and Procedure
The teacher will introduce vocabulary, and demonstrate how to
solve perimeter and area problems.
Introduction
Step 1. Activate Prior Knowledge
What do you know about perimeter and area?
What is perimeter?
The distance measured around an object.
Look at the objects below
You can use a ruler to measure shapes.
Perimeter
  Use the graph paper to draw some triangles and measure
  them.
Perimeter
The formula to solve a triangle is P = a+b+c
Perimeter

A         B




      C
Find the Perimeter
10cm          10cm   8cm         8cm



       10cm                8cm
What is the area?
The number of square units needed to cover a shape
What is the formula to solve the
area of a triangle?
A=½ hxb   or A= hxb
                 2

6cm



      4cm
Area
Find the Area
         5cm                    3cm



 4cm                              4cm
Area =                         Area =
Find the perimeter
P= 2L+2W

    5

5           5

        5
Find the Perimeter
    5cm              11cm



    5cm              11cm
Find the Area
A=LxW




        12 cm




4cm
Assessment
Compute the area, go to
http://www.mathgoodies.com/lessons/vol1/area-triangle-
part3.html
Compute the perimeter and area of shapes, go to
http://www.mathgoodies.com/lessons/vol1/perim_part3.html
Resources
http://www.helpingwithmath.com/printables/worksheets/geo060
1area02.htm
http://www.mathgoodies.com/lessons/vol1/area-triangle-
part2.html
http://www.michigan.gov/documents/mde/3rd_Math_357689_7
.pdf
http://office.microsoft.com/en-us/images/?CTT=97

Perimeter and area revised