The real issue here is that they are trying to teach a subject which is by itself already very abstract, with poor tools. C may be a fine language for doing low level work, but in this case low level is exactly what you should be striving to avoid.
I started programming at age 8 - and didn't know that it had a name. All I had was a Basic manual, then assumed that's how the computer was supposed to be used (no graphical interfaces at the time).
By age 11, I had moved from Basic to Turbo Pascal and was writing my own 'units' in Z80 Assembly.
However, despite several attempts, I could never grasp C for some reason, until university. And then it just clicked. It is as if some very important part of my brain was not ready yet for it.
I am not too fond of logo-like languages, except to teach the very young. I believe it is best to get them an environment which is already bootstrapped and ready to work, but that won't hold them back if they decide to do some exploring on their own, so it should be a 'real' language. But a simple one, such as Python or Lua.
The fact that they are starting out with C is borderline criminal and will backfire.