U4Ch1L3_Variables Practice

Purpose: Students will practice using the skills and processes they have learned about variables. 

Activity: Log on to U4Ch1L3 – Practice using all the skills you have learned.

• Level 1: Creating a Variable vs. Assigning a Variable
• View the program, then Run the program and watch it appear in the “Debug Console.”
• What is the difference between: “My Favorite Number is” & myFavoriteNumber
• What is the difference between: “My Favorite Food is” & myFavoriteFood 
• On which lines are the variables being created & on which are they assigned.
• Change the number that is assigned to the variable myFavoriteNumber and the string assigned to myFavoriteFood and run the program again.

Level 2: Variable Rules- There are a few Rules for Variables Names:

• Capitalization matters. myVar is not the same as myvar.
• Variable names can't have spaces in them. myVar and my_var are allowed but my var is not.
• Variables can't start with a number. var2 is allowed but 2var is not.
• Create a Variable only once.
• Create your Variable at the top of your program.
• Create your variable outside of an onEvent block.
• Now…Debug the Program!
• Add three lines to the story. Make sure you use at least one variable.

Level 3: Variables & Operators

• Run the program to see how it works.
• Three of the questions are missing code. Write expressions that evaluate to the correct answers. (Comments show you where to do it.)

Level 4: Variable in Expressions

Var. Hint:

• Variables can be created and assigned using a single command, like var myAge = 16.
• You can use variables in an expression, like myAge + 1.     but 2var is not.

• Do This:  Run the code to see how it works.
  • Which lines of code use a variable inside an expression? 
  • Does the value of the variable ever change? Why?
  • Add code that uses variables in expressions to complete the story. There are comments to show you where.

Level 5: Expressions: Joining Two Strings

Hint:
The  +  operator can be used to join two strings or a number and a string.

• "sun" + "rise" evaluates to "sunrise"
• "4" + "ever" evaluates to "4ever"
• The \n character ("new line character") will make a string print across multiple lines.

Do This:

• Run the program to see what it does.
• Write code to answer the last two questions. Join the strings to make your responses print on a single line.
  

Level 6: Counting with Numbers

Hint:
The counter pattern is myVar = myVar + 1. The expression on the right myVar + 1 is evaluated first. The new value is then assigned to myVar. This pattern lets a variable "count" by whatever amount is added.

Do This:

• Write code to make the "+$20" button work.

Level 7: Counting with Strings

Hint:
The counter pattern can be used with strings too.
Do This:

• Note a new block: getText() on line 14. 
• Add code so that each reminder is added to a different line on the screen. Remember the new line character is \n.
• Add code so that the reminder input is cleared out when you click the Remind! button.

Level 8: Global vs. Local Variables

Explanation

Level 9: Applying Your Variable Skills

Do This:

• Edit the three Apps using your new skills!