Every day I have been presenting free cartooning classes and quick draw jam sessions at howtotoon.com. I then compile the drawings into free coloring books you can download! Here is the link to number 5. You can also download books 1-4 on this page as well.
All of these are free to download but if you wish to make a donation you can here:
Donation to support Coloring Books by Joe Wos
Here is the latest edition. Quick Draw Coloring Book 4 as well as all the others.