"Factors"
Edwina R. Justice Gunsaulus Scholastic Academy
4420 South Sacramento Ave.
Chicago IL 60632
(312) 535-7215
Objectives:
Demonstrate a phenomenological approach to teaching mathematics
Inspire others to use the approach
Objectives (Grades 5-7):
Show and record groups formed by using pennies
Define factor, product, prime, and composite
Write related number sentences
Find the factors of whole numbers
Classify numbers as prime or composite
Identify abundant, deficient, and perfect numbers
Materials Needed:
paper coins (actual coins??)
worksheet for analyzing first moves
Recommended Strategy:
Ask: "How many ways can you make change for $1.00 using only groups of the
same coin?"
Expected responses: 1 group of 100 pennies
20 groups of nickels
10 groups of dimes
4 groups of quarters
2 groups of half-dollars
"How many ways can you make equal groups of 100 pennies?"
Expected responses: 1 group of 100 pennies
2 groups of 50 pennies
4 groups of 25 pennies
10 groups of 10 pennies
20 groups of 5 pennies
Discuss similarities in responses to both questions
Show one penny - Write "1 group of 1 = 1"
Show two pennies - Write "1 group of 2 = 2"
Show three pennies - Write "1 group of 3 = 3"
Show four pennies - Write "1 group of 4 = 4"
Show two groups of two pennies - Write "2 groups of 2 = 4"
Show and record all equal groups for 5 to 12 pennies
Write number sentences: 1 x 1 = 1; 1 x 2 = 2; 1 x 3 = 3; 1 x 4 = 4;
2 x 2 = 4; 1 x 5 = 5; 1 x 6 = 6; 2 x 3 = 6;
... 1 x 12 = 12; 2 x 6 = 12; 3 x 4 = 12
Define factor and product
Analyze number of factors for products 1 - 12
Identify and define prime and composite numbers for products 1 - 20
Play "Factor Game" - List the numbers 1 - 36 as a 6 x 6 grid.
Circle a number. Students draw a box around each proper factor
of the number. Students select a number and draw a box around it.
Teacher circles proper factors of the number. Continue process until
no moves are possible. Add the teacher's and students' numbers. The
highest total wins.
Analyze first moves for the factor game - List the factors for numbers
1 - 36. Compare the sum of the proper factors to each number.
Define abundant, deficient, and perfect numbers
Performance Assessment:
Select a two-digit number greater than 50.
Identify its factors.
Write related number sentences using the factors and the number.
Explain why the number is prime or composite.
Return to Mathematics Index