Demonstrate manipulating primitives with operators before manipulating them with methods so students can understand the basics of primitives before using them in a more complicated way.

Use the following two examples to help students reason about primitives in Java.
- This first example provides a good introduction to manipulating primitives in Java using operators.
  int x = 42; int y = x; x++;
- Ask students what the values of x and y are now. (Answer: x=43 and y=42). A common misconception is that both x and y are incremented because y=x.
This second example uses method calls to change x and y.
- Wait to show students this example until they understand how primitives are manipulated by operators.
  public class Sample { public static void main (String [] args) { int x = 42; int y = x; Sample.myMethod(x); } public static myMethod(int x){ x = x + 1; } }
- x=42. Have students reason through how the method affects x and y.

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