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Fraction Tutor

FractionTutor .sb2 For our last example, we’ll present an educational game for teaching frac-
tions. The interface for this game is shown in Figure 8-30. The player can
select an operation (+, −, ×, or ÷) and click the New button to create a new
problem. When the player enters an answer and clicks the Check button,
the Teacher sprite (image of a woman) checks that answer and provides an
appropriate feedback message.

Operation sprite
Digit sprite (invisible)
Read sprite

Teacher sprite

New sprite
Check sprite

Figure 8-30: The user interface for the Fraction Tutor application

The application contains six sprites. Operation allows the player to
choose a mathematical operation. Read shows the answer entry button,
New shows the New button, and Check shows the Check button. The Teacher
sprite checks the player’s answer, and an invisible sprite named Digit stamps
the numbers that correspond to the current problem on the Stage.
When the player clicks the New sprite (the New button), it executes the
script shown in Figure 8-31. The script assigns random values between 1
and 9 to the numerator and denominator of both operands, which are repre-
sented by the four variables num1, den1, num2, and den2. It then broadcasts
a NewProblem message to tell the Digit sprite to stamp these numbers on the
Stage.

Set numerator and
denominator of the
first operand.
Set numerator and
denominator of the
second operand.
Tell the Digit sprite to
show these numbers.

Figure 8-31: The script for the New sprite

206 Chapter 8
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