I was delineating two modes of failure. The first, and most obvious, is when your program won't run at all and you get a syntax error. That's what happens when you misspell something outside the quotes.

But if you misspell something inside the quotes, you get the second mode, in which your program runs but you get incorrect behavior.

For us this isn't a huge difference; they're both bugs. But for the girls it was huge. If their program won't run, it's busted, but if it runs but isn't quite right, well, that's what Microsoft charges $$$$ for.

I had to admit they had a point.

How about Bootstrap? http://www.bootstrapworld.org/materials/

I really think Scheme is only simpler if you have a really atypical kind of mind.

  (fn arg1 arg2 ... argn)

What sort of facilities can you build on top of that foundation to create an easy, accessible learning environment like Shoes?

They might be able to understand "later, rinse, repeat", or making a cake by making three layers, and then making the frosting, where each becomes a separate modular and reusable problem.

There's no need to worry about the precedence of operators, or indentation, or why you use one character to separate function parameters and variable declarations, but you use another character to separate the arguments of a "for" statement, which happens to be the same character you need to use at the end of statements (but as a terminator, not a separator), but don't forget that control structures are not separate statements even though they're on separate lines, etc.

Each of these points is an obstacle between the beginning programmer's intent and a running program. Scheme's almost total lack of syntax gets a beginning programmer started quicker.

To the average person, to make a toy car, it's straightforward to take a box, put on two axles, then put on two wheels. You could do all that with just toothpicks, but it's not really simpler in practice.