APCS Unit 2
Beginning Java
Beginning Java Introduction
Welcome to Unit 2

This unit begins our serious look at Java programming with a low-key introduction to the basics of a Java program, how to print text onto the screen, and how to deal with user input and simple mathematical operations. To program in our class we’ll use an IDE called “BlueJ” which is an excellent introductory program that will let us do all that we need to all year long!  All of our classroom computers already have BlueJ installed, but if you’d like to download it for yourself at home, the download link is available here on our website.

As we start our review of Java, we’ll take three major steps:

  1. Learn how to make a simple program that can print text in a variety of ways
  2. Learn how to take user input and save the user values as variables
  3. How to make a simple calculator using standard math operations

By the end of the unit, you should have the knowledge and skills to make simple text-based programs that can take and use user input in a variety of ways!


Part 1: Beginning Java

BlueJ Reference

The first part of this unit introduces BlueJ – our chosen Integrated Development Environment (IDE).  We’ll use BlueJ for the rest of the year as a good tool for writing, testing, and running programs. Our pass system and the cool light system in the room all run on BlueJ programs!

As our unit starts, you’ll get an introduction to BlueJ as a tool, as well as to the basic commands that we need to make a program work and to get things printing on the screen.  Then you’ll work through various programming challenges. Make sure to save each of them as you go!


 Watch the introductory videos about BlueJ, Java Programs, and Print Statements.  Take good notes, especially on the various commands that let us print things!

 Create a new project in BlueJ called “Unit 1” – you should store ALL of your Unit 1 programs in this same project.  

 Complete Java Task 1: 1-8 PrintLN

 Complete Java Task 2: 1-8 Print

 Complete Java Task 3: 1-8 PrintF

 Complete Java Task 4: Asterisk Shapes

 Complete Java Task 5: 10×10 Grid

 Have Mr. Benshoof check-off your completed Java challenges

 Complete the Java Assignment – you can view it here or you can get a paper copy from the hanging folders in our classroom!

What is Java?

Java Introduction 

Print Statements

Part 2: User Input

BlueJ Reference

The second part of this unit makes things a bit more challenging because your program needs to work on multiple maps without any modifications.  To make this happen, you need to teach your Jeroos to make decisions for themselves.  This works by using the “if” and the “while” commands.


Pro-tip:  Every one of the Advanced Challenges require BOTH ‘if’ and ‘while’ commands to write effectively.


 Watch the videos on control structures and take notes.  Review the “Jeroo Control Structure Examples” image to see the proper formatting for both the ‘if’, ‘if-else’, and ‘while’ structures.

 Complete the short “Jeroo Assignment”

 Complete Advanced Challenge 5: Hurdles

 Complete Advanced Challenge 6: Tom & Tammy

 Complete Advanced Challenge 7: Bugs & Daffy

 Complete Advanced Challenge 8: Flower Copy

 Have Mr. Benshoof check-off your completed Jeroo challenges

User Input

Scanners in Java

If Statements

Part 3: Calculator

BlueJ Reference

The final part of the unit has you take a short quiz and then tackle a Jeroo Super Challenge.  The quiz has 10 questions that ask you about Jeroo things and some of the simple programming commands that you’ve been using for the last few challenges.  You can use your notes on the quiz, but you must work by yourself!  You also only get 1 attempt at the quiz – so take your time and ask Mr. Benshoof questions if you have any!

Once the quiz is complete, you get to pick a Super Challenge.  The purpose of the super challenge is to make you think about all the tough aspects of really snarky programming problems.  Chances are, you might not have time to complete your chosen Super Challenge, and that’s okay – the real goal is to start trying to work on one and make a little bit of progress.

When you’ve either finished your Super Challenge or the unit deadline hits, go ahead and move on.  Wrap up the unit by writing the second AP Computer Science reflection log: Jeroo.  Write a full page in your engineering notebook about your Jeroo experiences. What did you learn from the simulation?  What was fun and easy?  What was frustrating or weird?  What do you want to remember moving forward?


Take the Unit 1 Quiz: Jeroo

 Pick a Super Challenge and brainstorm solutions, challenges, and ideas – record your thoughts in your engineering notebook

 Do your best to complete your chosen Super Challenge!

 Write APCS Log 2: Jeroo to reflect on your Jeroo experiences and what you’ve learned from it!

APCS Unit 2 Map
Looking for something?  Here you'll find a library of links to all the documents, images, and videos needed here in APCS Unit 2.