- Students can struggle with variables in computer science by thinking they work like variables in math.
- This activity is designed to help students understand the abstract concept of variables in computer science.
- Additionally, using age and other descriptive variables will help students distinguish between variables in different disciplines.
- When you use x, y, or z it is easy for students to get confused by thinking about variables in the way they’re used in math classes.
- You, the teacher, write lines of code on the board for your class (acting as the computer) to compute.
- This activity is built using Java but can be adapted to whatever language you’re teaching.
- Activity:
- Write the following on the board:
int age;
- Label a clear container age and place it on a table.
- Explain that this corresponds with creating a space in memory for your new variable.
- Then write:
age = 15;
- Next, write 15 on a sticky note.
- You can also use index cards or small pieces of paper.
- It is helpful to use sticky-notes because this allows you to copy the variable value to the board where you’ve written age = age + 1;
- Place the sticky note inside a tupperware container labeled age.
- Write:
System.out.println("you have a birthday");
age = age+1; - Go to the age container
- see 15 and get out sticky note, take it and place over the age variable in the right hand side of equation
- i.e. place it over age on the right hand side of
age = age + 1
; - Emphasize we do right side first then left side of assignment statement if they are stuck in math brain.
- now they see 15 + 1 and they mentally do the math
- Write 16 on a new sticky note
- Go back and replace the sticky note in the container
- So now we have a post-it note with 16 in the age container
- Notes:
- It is helpful to use the variable age, because they’ll be less likely to try to solve it like a math equation.