Everything you need to enjoy a brand new MCP23008 (MCP23008 library)
Need more pins on your Arduino? Maybe an I/O expander is what you need. These chips use the 2-pins of the i2c port to give 8 more in/out pins. You can have up to 8 of them share the same two pins for up to 64 additional pins! The trade off is speed (its about 50x slower to go through the expander than direct) and memory (the library takes up both RAM and flash). We wrote a handy library with examples of reading, writing and setting pullups for the inexpensive and easy-to-breadboard MCP23008.
Make a robot friend with Adafruit’s CRICKIT – A Creative Robotics & Interactive Construction Kit. It’s an add-on to our popular Circuit Playground Express, FEATHER and other platforms to make and program robots with CircuitPython, MakeCode, and Arduino. Start controlling motors, servos, solenoids. You also get signal pins, capacitive touch sensors, a NeoPixel driver and amplified speaker output. It complements & extends your boards so you can still use all the goodies on the microcontroller, now you have a robotics playground as well.