Introduction to Computer Science with Scratch and App Inventor

Variables and Keeping Score
Now that we have the start of a fun game, we want to keep score by letting our dinosaur earn a point
for every bowl of cheesy poofs that he eats. In order to do this, we are going to use VARIABLES.
A program can have many variables, each keeping track of a different value. In order to be able to tell
our variables apart, we give each variable a name.
Points:
23
To create a variable in Scratch,
go to the red Variables menu.
Then click on the Make a
variable button.
This will open a new box where
we can type the name of our
variable. Then click ok.
You can think of a variable like a chalkboard
that can store one number on it. We can read
the number off the chalkboard or write a new
number on the chalkboard, and it will always
keep track of the last thing we wrote down.
You always want to give your variable a
descriptive name that explains what
value it represents. Since we want a
variable that will hold the number of
points our dinosaur has, we’ll call our
variable “points”
mbrace Game Development Workbook Page 22