This question is in the context of teaching novices. For experienced
programmers, I have workarounds.

I would like to make all of the standard library available

     as a module based on module std

     with guaranteed range checking

     without requiring students to write std:: all the time

     and add a few supporting features

I have successfully done that for tens of thousands of students over
more than a decade using some disgusting macro tricks. Think

     #define vector My_checked_vector

Having guaranteed range checking is a great help to students. I estimate
that it eliminates more than 50% of crashes and lots of frustration.

Modules and disgusting macro tricks don't go well together

I was planning to use

     using vector = My_checked_vector

but I can't find a way for that to work together with

     using namespace std;

Am I being blind?

Any suggestions?

I can get away with a single #using "PPP_support.h" containing three
macros, but I would really like to avoid that.

I suspect the fundamental problem is that there is no way of composing a
module or a namespace saying "I want all of Foo, except that I want my
own versions of Foo::X and Foo:Y." I would *love* to be proven wrong
about that. The original namespace design had such a mechanism, but I
have not been able to get it to work.