It watches the button and keeps your score.
Arduino
The brain
Loading part…
Score Keeper
increment with ++ and --
Increment a score variable with a button press and print on Serial.
Pin connections
| Part 1 | Part 2 | |
|---|---|---|
Pushbutton pin 1 | → | Arduino pin 2 |
Pushbutton pin 2 | → | Arduino GND |
See it
Press to score points!
Every button press adds 1 to your score — your first number that grows when you push a button.
Arcade games, quizzes, and sports scoreboards add to a score just like this.
The story
The problem
The board needs to remember how many points you have earned so far.
Think of it like
It's like dropping a marble in a jar each time you score — the jar holds your total.
Meet the parts
How it works
1
Did you press the button?
The score only changes when you press — no press means no change.
if (digitalRead(BUTTON_PIN) == LOW)
2
Add a point
Take the old score, add 1, and save it back — the box remembers between presses.
score = score + 1;
3
Show the new total
Show the new score, wait for you to let go, then listen again.
Serial.print("Score: ");
Serial.println(score);Then loop back to step 1
Build the circuit
Follow these steps in order. Match the wires to the colors shown.
- 1
Place Arduino
Place the Arduino (uno) on the breadboard.
Arduino placed — ready to score!
Loading part…
Try it
- Tap the button — the screen shows Score: 1, 2, 3…
- Each press adds exactly one point.
Peek at code
The score box
const int BUTTON_PIN = 2; int score = 0;
score starts at 0 — a box that grows by 1 each time you press the button.
Get the button ready
pinMode(BUTTON_PIN, INPUT_PULLUP);
Serial.begin(9600);
Serial.println("Score Keeper — press to add a point");
}
void loop() {setup() sets up the button on pin 2 and opens the message screen.
Add a point on press
score = score + 1;
Serial.print("Score: ");
Serial.println(score);
while (digitalRead(BUTTON_PIN) == LOW) {
delay(20);
}
delay(150);
}
delay(20);
}
Press → add 1 → show the score → wait for release → listen again.
Show full sketch (score-keeper.ino)
const int BUTTON_PIN = 2;
int score = 0;
void setup() {
pinMode(BUTTON_PIN, INPUT_PULLUP);
Serial.begin(9600);
Serial.println("Score Keeper — press to add a point");
}
void loop() {
if (digitalRead(BUTTON_PIN) == LOW) {
score = score + 1;
Serial.print("Score: ");
Serial.println(score);
while (digitalRead(BUTTON_PIN) == LOW) {
delay(20);
}
delay(150);
}
delay(20);
}
Quick quiz
Q1. What is a variable?
- A. A named box that stores a number ✓
- B. A kind of wire
- C. Just a wait
Why: Yes! int score = 0; makes a box named score.
Q2. Why keep the score in a box instead of just printing 1 each time?
- A. So the total grows and is remembered between presses ✓
- B. Boxes make the light brighter
- C. The screen only works with boxes
Why: Yes! The box remembers the total even as the loop runs again.
Code lab — try on your own
Start at 10 points — change int score = 0 to int score = 10.
Hint: Line 2.
Add a note (comment) on the score line that says "add one point".
Hint: Line 12 inside the if.
Code walkthrough
A line-by-line tour of the sketch — the same steps as in Robot Gurukul Studio.
Program overview
Big idea
Every Arduino program has a top part, a setup() part that runs once, and a loop() part that runs again and again.
In this project
Each button press adds 1 to a score, and the screen shows the new total.
Tip
Read from the top to the bottom. Tap any word or line if you need help!
const int BUTTON_PIN = 2; int score = 0;
setup()
Big idea
setup() runs one time when the board turns on.
In this project
It gets the button on pin 2 ready and opens the message screen.
Why here
Things we do only once go inside setup().
void setup() {
pinMode(BUTTON_PIN, INPUT_PULLUP);
Serial.begin(9600);
Serial.println("Score Keeper — press to add a point");
}loop()
Big idea
loop() runs again and again, forever.
In this project
This is where we watch for the button and add a point each time.
Why here
Things that repeat go inside loop().
void loop() {
if (digitalRead(BUTTON_PIN) == LOW) {
score = score + 1;
Serial.print("Score: ");
Serial.println(score);
while (digitalRead(BUTTON_PIN) == LOW) {
delay(20);
}
delay(150);
}
delay(20);
}
Try this: Change a number inside loop(), then press Run to see what happens.
pinMode
Big idea
pinMode tells a pin if it will listen or push power out.
In this project
It sets pin 2 to listen for the button press.
Why here
It goes in setup() because we only set it once.
pinMode(BUTTON_PIN, INPUT_PULLUP);
digitalRead
Big idea
digitalRead checks if a pin is ON or OFF.
In this project
It checks if the button is being pressed.
Why here
It goes in loop() so we can react the moment you press.
if (digitalRead(BUTTON_PIN) == LOW) {delay
Big idea
delay means wait. Nothing else happens while it waits.
In this project
A tiny wait helps the button read cleanly.
Why here
Right after we check the button.
delay(20);
begin
Big idea
Serial.begin opens a message screen so the board can talk to the computer.
In this project
It lets us print the score.
Why here
It goes in setup() once, before we print anything.
Serial.begin(9600);
Big idea
Serial.print writes words or a number on the screen and stays on the same line.
In this project
It writes "Score: " right before the number.
Why here
In loop() so we can see each new score.
Serial.print("Score: ");println
Big idea
Serial.println writes on the screen and then jumps to a new line.
In this project
It prints a friendly hello when the board turns on.
Why here
So each message gets its own line.
Serial.println("Score Keeper — press to add a point");