Treasure trove of electronics textbooks from the 40- 50- and early 60ies in pdf-format. I am particularly a fan of the Audel’s Radioman’s guide, covering everything from basic electronics to the workings of aircraft radios of the 1940ies.
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.