Welcome to CS 124! Your journey in computer science and programming starts now. We’re so excited that you are here.
CS 124 has by far the best course staff on campus. Our fantastic team of undergraduate and graduate students will be with you every step of the way.
Learning computer science and programming is not always easy. You will get frustrated along the way. But you won’t need to struggle alone. Our course staff will always be there for you to offer help, support, empathy, encouragement, and lots of love. You can do this! We can help.
CS 124 consists of daily lessons and homework (30%), weekly quizzes (40%), and a longer Android programming project that we will release later in the semester (30%).
All course policies and procedures are fully documented by the syllabus. You should review that document and refer to it when needed. This section provides only a brief overview.
This semester you’ll work one lesson per day—just like this one. Lessons combine text, videos, code examples, and interactive walkthroughs. Interspersed are small programming exercises for you to complete.
We expect you to work through each day’s lessons on your own time. Don’t fall behind! Programming is a skill, best learned bit by bit, one day at a time. However, you may work a few days ahead, which can be helpful in case you need to take a few days off. You are expected to use this flexibility to plan around any absences.
Tuesday during your assigned section time you’ll take a proctored quiz. (Note that there are no other synchronous course activities.) Quizzes cover the material taught since the last quiz. If you have reviewed the lesson content and completed all of the homework and practice problems, you will be well-prepared.
Note that your first CS 124 quiz is today! Please review the forum announcements for more details about how to take your first quiz.
For the first few weeks of the semester we will proctor quizzes over Zoom and you will take them remotely, so you should not report to your assigned room to take your quiz. We may begin giving in-person quizzes later in the semester.
Around halfway through the semester we’ll release a larger multi-part Android programming assignment for you to work on called the machine project. The MP helps you continue to grow as a programmer and computer scientist by challenging you to complete a larger programming project—an entire Android app. We’ll get there! But let’s learn the basics first!
Learning to program is both fun and challenging, and CS 124 moves steadily. But to the degree that we challenge you, we also support you. Every step of the way.
CS 124 course staff are available for one-on-one help during scheduled hours using through the help site. The video above provides a brief demo. This is usually your best first step when you need help with your code.
You may also ask questions on our course forum. The forum is a hotbed of course activity, with staff and students available day and night to answer questions, commiserate, offer support, and engage in meme appreciation.
In addition to the lesson content, CS 124 many other ways that the staff help support you on your journey. Our calendar is the place to look for quiz review and preparation sessions.
Our lessons contain a mixture of different types of content. Some of each lesson will be text, like what you’re reading.
We also use a lot of interactive examples, like this one:
These playgrounds are editable and runnable. They are here for you to play with. Run them, modify the code, run them again. You’ll learn to program must faster if you allow yourself to experiment.
When working on larger examples your changes will automatically be saved, but you can always return to the original contents. You’ll know that an editor is saving your work when you see the green check mark in the upper right-hand corner, like this:
Sometimes we want to show you how to do something using code. In that case, we’ll provide an interactive walkthrough, which combines audio with an animated editor. Here’s an example.
Many of our walkthroughs include contributions from multiple course staff members. Confused? Try another explanation! Still confused? Ask on the forum or help site.
Finally, we’ll also sometimes use video to explain a concept or make a particular point. Or, for the staff to introduce some of their pets!
Mixed in to each lesson you’ll find practice problems, like the one below. Solutions to the practice problem will be available once you’ve attempted it a few times. These problems will help test your understanding as you go along, and prepare you for that lesson’s homework problem and related quiz questions.
As you learn to write computer code, you’ll need to be able to identify and fix small mistakes with your programs. To give you more practice with this, lessons also include debugging challenges, like the one below. These give you practice at finding and identifying small mistakes in computer programs.
Throughout the lessons—particularly on the Java materials—you’ll find explanations from Professor Colleen Lewis. Colleen is not officially involved with CS 124 this semester, but she created a bunch of great content in Fall 2021 that we continue to use. In general feel free to explore explanations from multiple staff members, particularly if the first one you see doesn’t quite click.
We’ll be reading and writing a lot of Kotlin computer code together this semester. But what is code?
Computers are incredibly powerful and versatile machines. If you can get them to do what you want, you can solve any problem and change the world. But how do we tell them what to do?
Here’s one of the simplest examples of a computer program—one so special that it has its own name: “Hello, world!“.
Run the code above and see what happens. Now, play with the code. Experiment and see what happens. Maybe try and see if you can get the code to print something other than “Hello, world!“. See if you can break the code, and find out what happens when the code doesn’t run. Nothing bad will happen! But see if you can figure out what is wrong with the code based on the output produced by the computer.
Each lesson concludes with a homework problem to complete. Solutions to the homework problem will be available once you complete it, or once the deadline passes.
CS 124 now allows students to collaborate freely on the homework problems. Please see the syllabus for more details.
Need more practice? Head over to the practice page.