I’ve just uploaded the latest version of SWFK. This fixes a few issues with continuity (such as referring to functions before they were actually explained), adds a basic explanation about the use of brackets and order of operations (which I think was a serious omission given the context), and other minor grammatical and code fixes.
The only major change is to add a few exercises to the end of some of the chapters, plus a new appendix for the answers. This is a work in progress. Exercises are currently missing from Chapter 9, and possibly aren’t as detailed (nor fun) as they should be.
But they’re a start…

Just downloaded SWFK. My kids are 8 so will be interesting to see if they can pick it up. I’ve been using Python for about a year myself with Enthought’s traits etc. I was actually googling for Python based maths software for kids when I came across SWFK
Hope you/they find it useful.
Hi Jason,
Great job! My daughter is 11 and she is having a ball with your book. We came across a situation in chapter 9 (a bit graphic) where the examples in Tkinter will not work as is because they are missing the final instruction, which is .mainloop()…unless we are misssing something.
Jason, do you think that the contents are stable enough to consider a translation? Since you already have a public repository, having the source there would be a very good thing translation-wise…
I think so. I still want to add more examples. And was thinking about splitting it out into more than one version, but I don’t have time to do either at the moment. So it might be a good idea to setup a repo for the latex source. Will do it once I get a chance.