I am not sure that this is a right fit for SE, but I will risk it.
I was recently acquainting myself with the
xy-pic package, and I found the included exercises very helpful in getting up to speed with the package.
It made me think how great it would be to have a set of TikZ exercises that aided getting used to the TikZ package since the size of that package has always daunted me.
I have been collecting TikZ examples over time, but I don't think it would provide the logical development that a set of well-constructed, consistent exercises might provide.
Any pointers to resources welcome.