It's always Python+X somehow, where X is a whole different thing you have to learn to get a fraction of the whole thing shipped in Python. Keep I.T. simple - teach the kids BASIC.
Python 2.7.9 (default, Dec 10 2014, 12:24:55) [MSC v.1500 32 bit (Intel)] on win
32
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>>> import turtle
>>> turtle.forward(100)
Isn't TK usually part of the standard library? Of course, then you have to build your UI in code, which can be a lot for a beginner - which I why I stated QML or GTK Composite Templates, both allow you to design your UI in the relevant tool (QtCreator, Glade) and then just wire it up. Speaking from experience, the trial and error of creating UI's in code instead of through a markup language with an editor that can preview it is a pain.
I don't really think GTK is that difficult to get a grasp on with composite templates. It's a little less "magic" than VB6 since I'm not just dumping code into a partial form class where the rest of the accessors to the COM controls are generated for me, but it's pretty straightforward in Vala right now (I use glade to design a UI, much like the classic WinForms designer - annotate a class with a GtkTemplate attribute and then put GtkChild attributes on class members to have the widgets automatically assigned there).
GTK in FreeBASIC is simple as well - just translate the C function calls into BASIC. FreeBASIC is really C++ without the curly braces so it's really a good covert way to gradually turn userland programmers into system programmers