Links

The following are a collection of my favourite tools/sites:

General

Pimoroni who sell all the amazing electronics devices used in our code clubs as well as designing some amazing stuff.
The PiHut who sell all things Raspberry Pi and other amazing electronics kits.
Cool Component who sell electronics and a range of other goodies.
Kitronik who are a specialist in electronic project kits.

Python in easy steps provides an excellent introduction to Python and is used as the reference book in my Python challenges.
Invent Your Own Computer Games with Python by Al Sweigart (available free online or in print from Amazon).
Python Programming Exercises, Gently Explained by Al Sweigart (available free online or in print from Amazon).
Making Games with Python & Pygame by Al Sweigart (available free online or in print from Amazon).
The Big Book of Small Python Projects by Al Sweigart (available free online or in print from Amazon).

PixilArt is an online paint program that is easy to use and supports transparency.
Piskel is a free online editor for animated sprites & pixel art.
Pixlr is a free online photo editor.
Vectr is a free online vector graphics editor.
Kenney free game art assets.
OpenGameArt.org free game art assets.

Invent With Python is a collection of wonderful books written by Al Sweigart and available free online.
MicroPython
CircuitPython which is a fork of MicroPython by AdaFruit and aimed as a beginner friendly version. See below for more links.
MakeCode Maker which offers blocks, JavaScript and Python based coding of microcontrollers.
Python micro:bit.
Pygame Zero is a framework for creating games without boilerplate.
Pygame Zero Helper is a Python module that provides a range of functions to make it easier to write Pygame Zero games. It has a particularly rich set of collision detection helper functions.
GuiZero is designed to allow learners to quickly and easily create Graphical User Interfaces for their programs.