Simple graphic library for beginners

[Jan Erik Moström]

I'm looking for a really easy to use graphic library. The target users 
are teachers who have never programmed before and is taking a first (and 
possible last) programming course.

I would like to have the ability to draw lines, circles, etc. Nothing 
fancy, as little window management as possible (possible buttons), 
perhaps simple events like button presses or clicks on canvas - think: 
making simple diagrams or simple figures. Cross-platform


Yes, I know about tkinter.

Yes, I know about various block languages like Scratch but they are not 
relevant in this case.

Any suggestions?

= jem