Christy Kirwan's blog

Using the Raspberry Pi for Educators

Dan Aldred is the author of Raspberry Pi Home Hacks, scheduled for release later this year, and the creator of the TeCoEd website, which contains free resources for teaching computer education. He is a computer science teacher, a freelance resource writer, a hacker, and a champion of the Raspberry Pi. He was kind enough to create this article with advice and tips for educators on using the Raspberry Pi in the classroom.

A Brief History of the Pi

Saturday, March 3rd, 2019 saw the Raspberry Pi’s seventh birthday celebrations trending on Twitter under the hashtag #PiParty. That Saturday marked seven years since the launch of the $35 computer the size of a credit card. To this day, the Raspberry Pi continues to be extremely popular with schools, makers, and tinkerers.

When people first hear about the Pi, they usually ask “How good can it really be? It only costs $35.” In a market saturated with smartphones and tablets that cost upwards of $500, anyone should be forgiven for questioning the performance of such an affordable product. Yet the evolution of the Pi has continued to surprise, from its original launch specs of 700 Mhz and 256MB of RAM to the current specs of 1.4 GHz and 1GB RAM. Impressively, it has kept the original $35 price tag. When was the last time that you purchased a new phone or laptop and paid the same price that it cost seven years prior?

The Pi Zero model, a $5 version of the Pi the size of a stick of chewing gum, is the most impressive iteration yet. The current Pi Zero W, which retails at around $10, is the same physical size but boasts a 1 Ghz processor and 512MB RAM (four times faster than the original Pi). In addition, it has onboard Wi-Fi and Bluetooth, which makes it a perfect board for hacks, projects, and builds.

Make Computer Science More Engaging

As an educator and teacher, I have found the Raspberry Pi to be an inspirational, motivational, and transformative tool for learning computer science. I had one student who self-described as dyslexic, “not very good at maths”, and “in need of a strong pair of glasses.” For eight months he attended my Raspberry Pi lunchtime club and was able to learn in such a way that he gained a world of confidence and went on a journey of personal transformation. Now he’s a confident student who enjoys the ‘logic of maths’ and has even developed a program used on the International Space Station.

In most situations, with the right support from teachers, students feel encouraged to try new things, fail, and keep trying. Students tend to feel the most empowered when the learning process happens through fun activities. This is where the Raspberry Pi comes in. Students are not ‘learning to code,’ but learning how to ‘hack Minecraft.’ They aren’t ‘calculating and coding’ a distance sensor but creating a ‘friend/enemy tracker.’ The versatility of the Pi means that projects, content, and theory can be adapted to appeal to a wide range of students, meeting their needs and abilities. Learning is accessible to all.

Easy to Maintain and Cheap to Replace

One frequent concern for teachers is, what happens if I’m using a Pi and the software fails or the SD card becomes corrupt? With a regular computer, teachers can normally notify tech support and have a malfunctioning computer repaired and returned within days. When using the Pi, malfunctions become a learning opportunity. Problems become chances to show the students how to flash an SD card, install an OS, and discuss what an .img file is. The process of setting up the Pi computer takes about 11 minutes and the next time they experience malfunctions, students will be able to fix it themselves by setting it back up again. If time is at a premium, simply keep a spare SD card in your pocket and swap it over, and the Pi can be up and running again in 30 seconds!

With a $35 price tag, lending students a Pi for the weekend is possible. The external engagement is priceless, even if students are just getting extra practice, and replacing a lost unit won’t break the bank.

Turn Theoretical Concepts into Practical Knowledge

The Pi is also a fantastic tool for learning about abstract concepts like networking. School computer networks are usually locked down. Students have no access to practice setting them up or configuring them. But teachers can easily bring in a few Pi computers and an old home router and get students to set up their own network. Using the OS command line, they can discover their IP address, ping each other, send messages, and even learn how to remotely shutdown another student’s Pi. Install a simple web server like Apache and let students build and host a website that can be accessed from the main school network. MAC addresses are accessible, and you can discuss the concept of spoofing one. Students are often only taught this information in theory. With the Pi in the classroom, they benefit from hands-on experience.

If you find that this approach to networking is still too dry for some of the students, let them set up and host their own Minecraft or Doom server. Once they’re hooked, move on to business and industry applications.

Give Students a Deeper Understanding of the Technology

The Pi grants your students access to the settings, network, GUI, hardware, and so on. This isn’t something to be intimidated by. Students aren’t learning anything if they can simply plug in hardware (a webcam, a flash drive, etc) and have it work perfectly. Modern technology is so user-friendly that any understanding of how the hardware really works is lost. I asked a class how the camera on their phone worked. One enthusiastic student’s hand shot up and they answered, “press the camera app symbol!” Correct, but, what is really happening when you tap the screen? Some argue we don’t need to know. I disagree. An inquisitive mind is healthy.

The computer keyboard is the distant relative of the typewriter, first released in the late 1880s. After over 100 years, remnants of the typewriter are still with us in our everyday keyboards, yet I have met students who don’t know how to type on a keyboard because they have only ever used the touch screens of smartphones and tablets.

With the Pi, students can dig in behind the scenes and see what is actually going on. They can learn to manage, configure, and control software and hardware in an intuitive way. Again, if this is not appropriate for a particular lesson, simply boot the GUI and students have differentiated access.

Acquire Affordable Ready-to-Use Hardware Attachments

One of the best hardware features of the Raspberry Pi is the set of 40 GPIO pins. These pins enable interaction with the environment, inputs, outputs, and lines of code. The Raspberry Pi has a wide range of affordable HATS (Hardware Attached on Top) designed to sit flush on the pins that add additional functionality and hardware to the Pi. One can buy everything from screens, LED matrices, and environment sensors to text scrollers, e ink displays, servo motor boards, and even pianos.

Projects My Students have Created with the Pi

Dan Aldred, computer science educator and author of Raspberry Pi Home Hacks

Lay-Flat Bindings: The What And How

lay-flat binding

You may have noticed that the spines of your No Starch Press books, even the ones you use most, stay free of creases. That’s because we pay extra to have our books bound with premium lay-flat bindings. Most No Starch books (with the exception of hard backs, some older books, and a very few print-on-demand titles) sport this nice little Easter egg.

Lay-flat bindings allow our books to lay open by themselves on a flat surface, making it easy to refer to them while working at a computer. As an added bonus, they keep the spines from developing cracks and creases with frequent use.

Here’s a somewhat technical explanation from our printer about how these special spines are manufactured.

Once a book has been printed and the printed signatures collected, the collated signatures enter our binder and are milled on the spine to prepare them for glue. There is a two-step glue process using PUR (polyurethane reactive) glue, the absolute strongest and most flexible book adhesive made, and EVA (ethylene-vinyl acetate) glue to adhere the covers. The milled signatures go across the PUR glue pot where glue is applied with two rollers:

PUR glue application

A reverse spinner roller then removes the excess glue:

glue leveling

The book then travels between two side glue rollers that apply a bead of EVA glue to the first and last page of the book. EVA glue must be used in this step because is adheres immediately to hold the book together whereas PUR glue must cure for eight hours before it reaches its maximum strength.

The next station is the krash station where the krash paper is applied to the spine of the book to cover the PUR glue film. This creates the gap between the book block and cover that is critical to provide the flexibility and lay-flat properties of this binding style. Finally, a cover is applied which is adhered to the book with the side glue at the front and back corners of the spine.

The books are then inspected for quality issues and shipped off to our distributor, bookstores and of course, to you.

The Very First No Starch Press Book: The Book of SCSI

photo of The Book of SCSI

It’s January of 1995. Boyz II Men have the #1 hit song, Braveheart is in theaters, and Dr. Martens are à la mode. No Starch Press has just published its very first book of all time, The Book of SCSI: A Guide for Adventurers. The guide was a meticulously researched comprehensive SCSI resource that featured no-BS explanations for beginners in plain English as well as deep dives into the technology by experts. While decades out of date, this book set the tone of No Starch books to come with its conversational approach, attention to detail, careful fact checking, and fun aesthetic. Its table of contents included:

  • An intro to the basics of SCSI
  • Instructions on how to add SCSI to your PC
  • An explanation of how the SCSI bus works
  • Overviews of ASPI programming and CAM programming
  • Q&A from major SCSI host adapter manufactures Adaptec, DPT, and Future Domain
  • A directory of 150+ companies that produce SCSI hardware and software
  • A look at SCSI into the future by John Lohmeyer, chairman of the ANSI SCSI-3 Committee and world’s leading SCSI expert
  • Drawings and diagrams of SCSI hardware and systems
  • Tips and troubleshooting help
  • A glossary of terms
  • A comprehensive index

Neither the original, nor its 2nd edition, released in the summer of 2000, are still in print, but both were well-regarded at the time (the original release was even reviewed by PC magazine).

Cheers to the OG No Starch fans who threw on a flannel and headed to the Computers section of their local Waldenbooks to pick up a copy.