Raspberry Pi Shopping List

The Raspberry Pi is a $45 computer.  Trouble is, it needs more stuff to make it go.  This Raspberry Pi shopping list will help you be sure you have all the essentials and will suggest add-ons that will let your students do more experiments and build more things.  Many of the prices below are from the spring of 2019.  If you find problems with this list, please tell me by writing to Bob.Brown@Kennesaw.edu.  I want to correct errors and make this a truly useful list.

I recommend one Raspberry Pi with parts kit for every two students; that allows students to work in pairs and learn from each other.  I've made a list of precautions your students should read.

The Bare Minimum

Although there are ways to connect remotely to a Raspberry Pi, students will learn best if they can put their hands on the equipment.  The items on this list will allow one pair of students to use a Raspberry Pi and perform simple build-it experiments, such as making one face of a traffic light.

A Raspberry Pi:  The newest, latest, greatest, and coolest Raspberry Pi (as of spring, 2024) is Raspberry Pi 5.  However, they have a minimum price of about $80... if you could buy one; they out of stock in most places.  For K-12 schools, I recommend the Model 4 B.  It has a faster processor and, for more money, more memory.   For a single purchase, get a Pi 4.  For classroom use, if you're just starting out, get the Pi 4.  If you already have some Raspberry Pis and you're not going to do a wholesale replacement, you may want to stick with the Model 3 B+.  The reason is that the power supplies, cables. and cases used with the Pi 3 won't work with the Pi 4.  Both models are available from Adafruit, which also has the power supplies recommended below, with a limit of two per customer.  In other than pandemic times, Arrow often has them in quantity with free shipping. Newark and Chicago Electronic Distributors usually have quantities available, as does Microcenter.

I've recommended the Model 3 B+  or Model 4 because they have on-board Ethernet, four USB ports, and there are lots of accessories for them.  The Pi Zero and Pi Zero W are less expensive individually, but you'll end up paying more in the long run because of the add-ons you will need. 

A power supply:  The Model 3 B+ needs a 2.5 amp power supply with heavier-gauge wire than one finds in phone chargers.  Adafruit has the right power supply for $7.50.  There's a check-block in the link to buy a Raspberry Pi that will add one to your order automataically.  The Pi 4 needs more power and a USB-C  connector, so power supplies for the Model 3 B+ will not work with the Model 4.  Because of a quirk in the way the Pi 4's power circuitry was designed, not all power supplies will work on Pi 4s made before about December, 2019 even if they have the right connector.  For the Pi 4, get the official Raspberry Pi Foundation power supply.  These should be available from the same place you get your Raspberry Pis.

Don't skimp on power; your Raspberry Pi might run erratically or not at all with an inadequate power supply.  Note: Although the connectors are the same, most cell phone chargers will not provide sufficient current to run a Raspberry Pi.

An SD card, possibly with operating system:  In place of a hard disk, the Raspberry Pi uses a micro SD card,

Two micri-SD cards
such as might be used in a camera.  The Raspberry Pi Foundation recommends the SanDisk brand. You can buy cards with an OS installer already loaded, but you can save money by buying a five-pack of blank SD cards for less than $36 and installing the operating system yourself.  A larger card probably isn't necessary unless you are doing something unusual, such as duplicating multiple cards.  You can get a blank 64GB card for $10 from Amazon; 32 GB cards cost only about $8.00 each in packs of two. If you need more than a few, we've been very happy with cards from Bulk Memory Cards.


You will also need a microSD to USB adapter to work with these cards on a desktop computer.  The five-pack in the link above includes a suitable adapter.

It's important that you get a Class 10 micro SD card. That will have a symbol that's the letter C with the number 10 inside it.  Not all cards work.  There's a compatibility list, not by the Raspberry Pi Foundation, available.  My suggestion: Get the 16 GB blank cards, in a batch so they're all alike, and load your own O.S.  You will need a few extra cards.  Students can corrupt an SD card by turning off power without a clean shutdown.  You can correct the problem by reloading the card, but you'd like to give the student a new card while that's happening.

An operating system:  Even if you buy an SD card with the OS installed, you will want to re-install the OS every term because your SD cards will have old student work on them.  The Raspberry Pi operating systems are free to download, and the Raspberry Pi Foundation has instructions for downloading and installing an OS.  Use Raspbian, not NOOBS.  Be sure to set aside some time if you need to do 15-20 installs!  We've written some instructions for duplicating multiple SD cards.

You can download the latest version of the OS image we use in our workshops, and other goodies as well, from our Raspberry Pi Resources page.

A USB keyboard and mouse:  You'll need a USB keyboard and mouse for each Pi.  (Bluetooth works, too, but wired devices will be much less fiddly in the classroom.)  You can probably find these in a closet at your school.  If not, a generic keyboard/mouse combo will cost $15 from Amazon.  If you have a little extra cash, the official white and raspberry red keyboard and mouse combo is available from CanaKit for $25.

A monitor and cable: The Raspberry Pi video output is in HDMI format.  If your school has HDMI monitors, you're good to go!  Just plug the HDMI cable into the Raspberry Pi.  If money is burning a hole in your pocket, you can get a 20" HDMI monitor for $80.  Bigger ones will cost more.  You'll also need an HDMI cable for about $7. For the Pi 4, you need a cable with a micro HDMI connector on one end and a regular HDMI connector on the other.

No HDMI monitors and no money?  Your school's monitors probably have DVI inputs.  If so, you'll need an HDMI to DVI cable for about $7. This one is for the Raspberry Pi 3. For the Pi 4, you need a micro HDMI to DVI cable.  The DVI connection doesn't carry the audio signal, so you may need an audio cable or headphones as well if you're doing things that require sound.  You may need to enable audio on the headphone jack.  Right-click the volume control (speaker icon) on the top right of the screen and click "analog" if "HDMI" is selected.

There are HDMI to VGA converters, but not all of them work well.  If you have to go that route, be sure to read the reviews, looking for "works with Raspberry Pi," before you order.  I've tested this one and it seems to be OK.  It's less than a foot long, so you'll need a regular VGA cable, too.  If you have VGA monitors, you probably have suitable cables.  The VGA connection doesn't carry the audio signal, so you may need an audio cable or headphones as well if you're doing things that require sound. You may need to enable audio on the headphone jack. Right-click the volume control (speaker icon) on the top right of the screen and click "analog" if "HDMI" is selected.

Have laptops or desktops but no monitors?  You may be able to use a laptop or desktop computer instead of keyboard, mouse, and monitor.  It will take some special configuration.

Parts!  The whole point of the Raspberry Pi is for kids to build stuff; otherwise, it's just another computer.  An education parts kit for about $23 will let students experiment with LEDs, a pushbutton, a buzzer, a couple of sensors, and other material.  You probably want to consider these to be expendable and plan on buying new kits every year or two.  Our friends at Low Voltage Labs make a similar parts pack, available through Amazon, without the temperature and motion sensors.

A GPIO reference card:  This is a small plastic gadget that slips over those 40 GPIO pins and provides labels for them.  Without it, your students absolutely will damage your Raspberry Pis by connecting the wrong pins.  Both education parts kits in the link above include a GPIO reference.  If you have a parts pack without the reference, you can buy them on Amazon in packs of 25 for about a dollar each.  There's also a printable image that will let you make paper references.  Try printing on index card stock if available, and be careful forcing the pins through the paper.

A case, maybe?  You can find many cases for the Raspberry Pi, and most starter kits include a case.  You don't need it.  If your students are building stuff, they'll work with the Raspberry Pi out of the case anyway.  Instead, pick up a plastic storage box like these for two dollars or so each or see what the Container Store has.  (If you want to store cables, too, you'll need a bigger box.)  You probably want to put each Raspberry Pi and its SD card in an anti-static bag for storage.  Twelve bucks will get more than you can ever use!

A base instead of a case? The very nifty 3D printable Pi Plate from Thingiverse will keep your Pi 3 off the desktop and provide some protection from short circuits.  That's for the Pi 3 only.  KSU's own Rachel J. has adapted the Pi Plate for the Pi 4.  You can get Rachel's adaptation here.

But I really want a case!  OK, look into Pimoroni's Pibow Coupé 3 B+.  At $10.00 plus shipping, it will add nearly a third to the cost of the Raspberry Pi itself.  However, it is cool, and it protects your Raspberry Pi while leaving all the hackable stuff accessible to your students.  It also provides protection against short circuits, particularly on the bottom of your Raspberry Pi.  Some Assembly Required.™ Beware: This case will not fit a Pi 4.  Also, not all versions of this case will work with the Model 3 B+; you need part number PIM341.   Adafruit has a similar case that's less expensive, but not quite as cool.

There is a similar Pibow Coupé case for the Pi 4, but it lacks the markings for the GPIO pins, so it's much less useful to students.  The niftiest case we've seen for the Pi 4 is the Argon NEO.  It's a bit pricey, though.

If you have 3D printing capability, you might let your kids print Raspberry Pi cases.  Be careful, though; cases for the Pi 3 will not fit a Pi 4.

Bottom line:  If you have keyboards, mouses, and DVI or HDMI capable monitors, you can equip each pair of students for $80-90.  You may be able to bring the prices down further with education or quantity discounts.


Very Cool Extras

With the material above, students will be able to make lights blink, buzzers buzz, and detect things in the physical world. To do more things, students will need more stuff.  Depending on how you organize your class, you may not need one of these for each pair of students.  For example, you may have some students working with the Sense HAT and some working with the Explorer HAT.  (HAT is a somewhat tortured acronym for Hardware Attached on Top.  It sits on top of the Raspberry Pi just like, um, a hat.)

Motors! ...and motor controllers: Kids love to make things go, and an early request is likely to be for motors, wheels, and gears.  There are three kinds of small motors, and you will want to choose the kind for your application.  DC motors can run forward or backward, and the speed can be controlled by turning power on and off very quickly, a technique called Pulse Width Modulation.  Servo motors can be commanded to rotate to a specific angle, so they can be used to do things like open and close doors.  Stepper motors can be precisely controlled, like servo motors, and can also rotate continuously.  You probably want to start with ordinary DC motors, perhaps like this one for $4, and progress to the other types as requirements dictate.  You will also need a motor controller like the Explorer HAT that's just below.  Other kinds of controllers may need a battery pack to power the motor independent of the Pi's power supply.  Powerful motors will also need a battery pack.

Explorer HAT: Add motor controls, inputs, outputs, and touch switches to your Raspberry Pi with the Explorer HAT. $23.

Robot Rover: Put your Pi on wheels with the Robot Rover. For younger kids, this pre-fab chassis will put them on the road to building a robot.  In addition to the Rover itself, you'll need something like the Explorer HAT and a battery pack. $25 for the chassis only.  Older kids might design and build their own robot chassis.  The Raspberry Pi Foundation has a robot project to get them started.

Distance sensors, also called rangefinders, and light sensors may be needed for work in robotics.  The parts kit in the "Bare Minimum" section includes temperature and motion sensors.

More parts:  Students will let all the smoke out of a few LEDs every year, and they may want parts not in the "Bare Minimum" kit above.  SunFounder makes several parts kits, like this one, that let students do more with their Raspberry Pis.  Multiple prices; the one in the link is $36.

Camera board:  Take still pictures and videos with the camera board.  The board itself is $30.  Accessories include cases, tripods, and pan/tilt housings.  There's also an infrared camera.

Camera with interchangeable lenses: In spring, 2020, the Raspberry Pi Foundation announced a new, high-quality camera that has a 12.3 megapixel sensor and accepts C or CS mount lenses.  The camera is $50 and you'll need a lens, which is another $25 or more.  You can download the official Camera Guide free as a PDF.  Printed copies are about $15.  Although much more expensive than the original PiCamera, which is still available, this accessory permits truly high-quality pictures.

Sense HAT:  Measure temperature, pressure, humidity, and orientation with the Sense HAT and display the results on an 8x8 RGB LED matrix.  $40.  There is a Sense HAT emulator in the Raspbian operating system.  Students can test and debug using the emulator, then demonstrate with a physical Sense HAT.  That way, one Sense HAT module can do for an entire class.  There's even a web-based Sense HAT emulator that your students can try with just a web browser.

Piano HAT: Use the Piano HAT to make beautiful music with your Pi with an octave of piano keys plus more touch-sensitive controls and programmable LEDs.  $20.  You will need speakers or headphones to plug into the audio jack if you want to do anything with music or sound.  Pro tip:  Your classroom will be much calmer if you get headphones.

Many more HATs:  You will find page after page of HATs at Adafruit, and a search will find even more.

Much, much more!  Try "raspberry pi add-ons" in your favorite search engine and you'll find hundreds of things to add fun to your Raspberry Pi.

Last update: 2024-02-02 12:21
Originally published: 2018-09-25