Java Tutorial

Java Project: Grade Calculator

Convert numeric scores to letter grades, compute a GPA-style average, and print a report.

What you will build

Map a number to a letter, then average the scores.

Letters and average

Example

public class Main {
  static String letter(int n) {
    if (n >= 90) return "A";
    if (n >= 80) return "B";
    if (n >= 70) return "C";
    if (n >= 60) return "D";
    return "F";
  }

  public static void main(String[] args) {
    int[] scores = {91, 84, 73, 68};
    int sum = 0;
    for (int n : scores) {
      System.out.println(n + " " + letter(n));
      sum += n;
    }
    System.out.printf("average: %.1f%n", sum / (double) scores.length);
  }
}

Practice

  1. Compile the complete program at /java/try.
  2. Change one input value and compile again.
  3. Replace a hardcoded number with Scanner when you want typed input.

FAQ: Java Project: Grade Calculator

Common questions about this page.

What is the StudyGrid Java tutorial?

The StudyGrid Java tutorial is a full beginner-to-advanced track: syntax, types, input, loops, methods, classes, collections, generics, maps, and lambdas. Each chapter has copy-and-run examples.

Should I run java grades project examples locally for better learning?

Yes. Use the browser editor on StudyGrid for a quick check, then Download the example and run it on your computer. Local runs show real errors and the real toolchain, which is one of the fastest ways to learn java grades project in this Java Java lesson (Java Project: Grade Calculator).

Is the Java editor the same as Try Python or Try C++?

No. Try Java compiles with javac at /java/try and shows stdout plus compiler messages. Try Python stays at /try. Try C++ stays at /cpp/try. Java lessons never open those editors.

Do I need to install a JDK to learn Java?

No. Open a chapter, click Try it in Java, and compile in the browser. You can also download a .java file and compile locally with javac.

Where should I start the Java tutorial?

Start at Java Intro, then Get Started and Syntax. After the first program, continue to output, variables, and if-else. After classes, open Java Examples, then generics, map, and lambdas. Use Next at the bottom of each chapter.

Is the Java tutorial free?

Yes. The Java workshop on StudyGrid (studygrid.in) is free: dashboard, chapters, and the compile-and-run editor.