I want to contribute to the Hour of Code event happening now during Computer Science Education Week.

I don’t write about computer programming, but I do write extensively about how computers work — in particular, about how they do arithmetic with binary numbers. For your “hour of code” I’d like to introduce you to binary numbers and binary addition. I’ve selected several of my articles for you to read, and I’ve written some exercises you can try on my online calculators.

## Binary Numbers

I’ve taught binary numbers to first graders, I’ve taught binary numbers to third graders, and I’ve taught binary numbers to adults. Read those articles and then try these problems:

- Convert 45 to binary.
- Convert 1001101 to decimal.

Use my decimal/binary converter to check your answers.

## Binary Addition

Read my article on binary addition, and then check out my article on the Binary Marble Adding Machine to see it in action. When you are done reading, try these problems:

- Add the binary numbers 111 and 110.
- Add the binary numbers 1011 and 101.

Use my binary calculator to check your answers.

(Don’t cheat and convert those numbers to decimal first and *then* add them — although that is a good way to check your work.)

## If You Have More Than An Hour…

See what binary numbers look like and what binary numbers sound like.