MicroBlocks runs on a wide variety of microcontroller boards. This page highlights some that are especially useful for learners and educators.
The micro:bit is one of the most popular microcontroller boards for education. Over five million micro:bits have been distributed in over sixty countries (ACM 2020) and the micro:bit Educational Foundation reported that over twenty million students have used micro:bits as of 2019.
The micro:bit has a rich set of features, including two buttons, a 5x5 LED array that can display graphics and text, a radio that supports peer-to-peer messaging, and sensors for light, motion, and temperature. The micro:bit also has an edge connector that allows additional devices to be connected if desired, but adding components is not necessary. The many built in features of the micro:bit allow beginners to do interesting things immediately without wiring. That simplicity allows the micro:bit to be used by elementary school children (grades 3-5) as well as teens and adults. The micro:bit has a low floor and a high ceiling.
MicroBlocks supports both the original micro:bit and the new micro:bit v2, which adds a speaker, microphone, touch sensor, and other improvements to the original design.
The Calliope mini is a German variant of the micro:bit, with a few changes and extensions. The most obvious change is the shape of the board, which was optimized for use with alligator clips. The Calliope mini also has a built-in speaker, a microphone, and an RGB LED. While it lacks the micro:bit's edge connector, it has two Grove connectors for connecting additional components.
In the US, the Calliope mini is available from Adafruit.
The Adafruit Circuit Playground Express and Circuit Playground Bluefruit are also popular with educators. These boards feature a set of buttons and sensors similar to those of the micro:bit, but replace the 5x5 LED display with a circle of 10 programmable RGB LED "NeoPixels" than can be used to create colorful, eye-catching animations. These boards also have good built-in speakers and eight alligator-clip friendly GPIO pins. Less obviously, these boards have beefy power supplies that can drive multiple external devices such as servo motors or NeoPixels strips making them especially useful in art projects.
The Circuit Playground Bluefruit (but not the Express) has a radio that can communicate with the micro:bit and Calliope mini.
The ED1 board and the related robot kit were developed by the Citilab Cornellà EduLab specifically for K-12 education. EduLab has led workshops for thousands of school children in the Barcelona area using MicroBlocks on the ED1. Over the past several years, the ED1 board and robot kit have gone through multiple design-and-test cycles, and it shows. Their robot uses stepper motors (the motor controller is built into the board) for precision. As a result, it can turn and move by exact amounts and, when dragging a pen, is capable of drawing geometric figures accurately.
The ED1 has a 128x128 TFT display that can be used to display text and graphics. There is even a Logo Turtle library for it. The display can simulate the micro:bit's 5x5 LED display, so the ED1 can run micro:bit programs. The board includes a nice built-in speaker, six touch buttons, motion, light, and temperature sensors, an IR receiver, and a set of GPIO pins for connecting additional devices.
Finally, the ED1 supports WiFi. Using MicroBlocks libraries, you can create a small HTTP server that you can use to remotely control the ED1 from a web browser or from a Snap! program.
The Clue, a new board from Adafruit, was recently featured on the cover of Make: magazine. Like the ED1, it has a TFT display (240x240) and speaker. It also has an impressive collection of built in sensors (motion, magnetometer, proximity/light/color/gesture, sound, humidity, temperature, and barometric pressure/altitude) and features a radio that can interoperate with the micro:bit. A useful feature of the Clue is a micro:bit-compatible edge connector, allowing the Clue to can take advantage of extension boards created for the micro:bit.
M5Stack products feature plastic cases that make them look more like consumer products than most microcontroller boards. The M5Stack Grey features a large TFT display (320x240), three buttons, motion sensor, speaker, WiFi, and a built-in rechargeable battery. A set of GPIO pins are accessible through slots in the sides of the unit. The M5Stack Basic Core model is similar to the Grey model but omits the motion sensor.
The M5 Stick-C features a tiny TFT display (160x80), a motion sensor, two buttons, an IR transmitter, WiFi, and a small rechargeable battery. Small and light, the M5Stick-C can be worn on the wrist and used to create your own fitness device or smart watch.
The M5 Atom Matrix is tiny -- only one inch (24 mm) square! Instead of a TFT display, it has a 5x5 grid of programmable RGB LED's and the entire top is a button (but that's the only button). It has a built-in motion sensor, an IR transmitter, and WiFi, but it does not have a built-in battery.
Created by the Chinese company Espressif, the ESP8266 and ESP32 are WiFi-enabled microcontroller modules that are used by most of the WiFi-capable boards that MicroBlocks supports. Those modules are also available in inexpensive bare-bones boards designed for electronics hobbyists such as the NodeMCU (left), ESP-32S (center) and Wemos d1 mini (right). Such boards don't have much built in -- at most a single programmable button and one or two LED's. They are designed to be plugged into an electronics prototyping board and connected to additional components. Since some wiring is required to make these boards do interesting things, they have a steeper learning curve for beginners than the other boards listed here.
However, their low cost and WiFi capabilities makes these boards useful for advanced students or makers who want to explore IoT applications. It's a good idea to check reviews before buying one of these boards. Some boards are too wide to be conveniently used in electronic prototyping boards while others lack USB-serial chips.
In addition to the boards listed here, MicroBlocks runs on many other boards. You will need to compile and install the MicroBlocks firmware for those boards yourself using PlatformIO or the Arduino IDE.