[Class Report] Introduction to System Development – Week 2: Taking on Variables and Calculations!

The second week of system development class for first-year high school students took place. Following last week’s lesson, “Let’s Talk to the Computer Using print,” this time we dive into the mechanism of “memory” in programs.

■ Today’s Theme: “What Are Variables?”

Mr. Tanaka opened with an intriguing question.

Mr. Tanaka: “Everyone’s used a notepad before, right? Variables are like a ‘notepad’ in a program.”

Student reactions varied.

Student A: “Wow, programs can make notes too!”
Student B: “Wait, is that different from saving data?”

Using diagrams on the whiteboard, Mr. Tanaka explained that variables are like “boxes that temporarily store information and let you retrieve it when needed.”

■ Exercise ①: Let’s Assign a Value to a Variable!

The students’ first hands-on experience with variables in Python began with this code:

x = 10
print(x)

Mr. Tanaka: “This program puts the value 10 into a variable called x, then displays it.”

When the students typed it in…

Student C: “Whoa! I wrote x, but it showed 10!”
Student D: “It’s kind of like giving something a name and calling it!”

■ Exercise ②: Let’s Do Calculations with Variables!

Next, they took on calculations using variables:

a = 5
b = 3
print(a + b)

To help them understand what values were in a and b and how the calculation worked, Mr. Tanaka stressed the importance of “writing out the steps.”

Mr. Tanaka: “Programs don’t just spit out answers instantly. Like humans, they go through each step, one at a time.”

Student E: “It’s kind of like a calculator, but it’s fun because you get to give the instructions yourself.”

■ Silent Work Time: Tackling Mini Challenges!

In the latter half of class, students worked on some “mini challenges.”

💡 Sample Tasks:

• Store your age in a variable and display your age five years from now.
• Calculate and display the total cost of purchasing Product A (120 yen) and Product B (150 yen).

Focused typing filled the classroom, and from time to time, voices of success rang out: “I got it!”

■ A Word from the Teacher

“Variables are a key part of giving ‘meaning’ to programs. Once you get the hang of it, try giving your variables meaningful names too.”

■ Sneak Peek: Into the World of Conditional Branches!

Next week’s theme is “if statements.” We’ll begin teaching programs how to “think.”
“If the weather is sunny, go outside,” or “If the score is 80 or higher, pass”—soon, your programs will be able to make those kinds of decisions!

The first-year students are gradually discovering the fun of programming. Stay tuned for next week’s class!