Teaching Algebra with Manipulatives

Chapter 4 Teaching Notes and Overview
Materials
scissors
several pieces of string
Prior to the activity cut the pieces of string.
Form student pairs. Emphasize the importance
of reading the steps to collect the data. Monitor
each pair and ask questions. As soon as the
pairs have completed the activity, discuss the
answers to the exercises. Have the pairs explain
their answers.
Answers
See Teacher Wraparound Edition p. 241.
Algebra Activity
Functions
(pp. 91–92 of this booklet)
Use With Lesson 4-8.
Objective Write an equation given some of the
solutions.
Materials
classroom set of Algebra Activity worksheets
transparency master of Algebra Activity
Display the transparency master of the Algebra
Activity. Discuss the diagram of a function
machine. The function rule is computed for each
“x” input that yields “y” as its output. Next,
show the first line of examples where f(x) x 2.
Uncover the second line of function machines
where f(x) 3x 2 and ask students for the
values of y (the output). Using the third line of
function machines, guide students to develop
the function rule f(x) 2x given the values in
the table.
Play the Function Machine Game as follows.
Player A thinks of a rule and acts as a function
machine to compute a new number y from x
given to them. (Record x and y on the chart for
each computation.) When a student wishes to
guess the rule, they must first give an example
for x and y. If correct, they may give the rule
and write the equation. The winner of each
round becomes player A and the game
continues.
Use the Algebra Activity worksheet for guided
practice for group or individual instruction.
After the students have completed the
worksheet, discuss the answers.
Answers
1. y 3x
2. y 0.5x
3. y x 4
4. y x
© Glencoe/McGraw-Hill 84 Teaching Algebra with Manipulatives