Introduction

Welcome to the From Scratch Programming Class — a free class for kids and teens, and the textbook that goes with it.

This book is a record of everything we cover in class, written so you can read it on your own. Every chapter matches one class session. If you went to class, the chapter is your reference for what we did. If you missed class, the chapter is how you catch up.

How to use this book

Read it whichever way works best for you.

• Reading after class. Skim the chapter to remind yourself what we covered. The exercises you did in class are written out here so you can do them again or finish what you didn’t get to.
• Reading because you missed class. Look for the If you missed this session section near the end of the chapter. It’s a shorter, self-paced version that gets you ready for next week. Should take about twenty or thirty minutes.
• Reading ahead. Some students like to read the next chapter before class. That’s fine, even encouraged. Reading ahead doesn’t excuse you from doing the in-class exercises — that’s where the thinking happens — but coming in with questions is great.

How chapters are organized

Every chapter is built the same way:

1. What we’re learning today. A short paragraph or two on the point of the session.
2. You’ll need to remember from last time. A few bullet points from previous sessions you’ll lean on today.
3. Part A. A new concept, with a guided exercise.
4. Part B. Practice or a small project that uses Part A.
5. Wrap-up. A few questions to think about.
6. If you missed this session. The catch-up version.
7. Stretch and extension ideas. Optional extras.
8. What’s next. One sentence on where we go from here.

If class gets cut short, Part A always stands on its own. You’ll miss the practice in Part B, but you’ll have everything you need to keep going next week.

A note about asking for help

Two rules in this class:

• Ask your buddy first, then Mr. Eric. It cuts down on people waiting and makes you better at explaining what you’re stuck on, which is half of figuring it out.
• You’re done when you can explain how it works. Not when the code runs. Not when it looks right. When you can walk someone else through what your program does, line by line, you’re done. Until then, you’re not.

A note about the curriculum

This book covers about 150 hours of class — anywhere from one to two years, depending on how often your class meets. It starts with Scratch and ends with small web applications you can run in a browser. You don’t need to know anything to start. You don’t need a computer at home — most classes provide one for you to keep.

If you’re reading this years after taking the class and trying to remember how to do something, the search bar at the top of the site is your friend. The book is here for you whenever you need it.

Now turn the page. Or click the next arrow. Either way, let’s go.