[plt-scheme] Using check-expect in the module language

I'm trying to use the check-expect form from the teaching languages in the module language, but it doesn't work the way I expected.  For instance:

>
> #lang scheme
> 
> (require test-engine/scheme-tests)
> 
> (define (double x)
>   (* x 2))
> 
> (check-expect (double 10) 30.2)
> 

Doesn't report an error.  What do I need to do to get it to report the error in the same form as in the teaching languages?

Thanks,

Mike