csh script help

To aid in debugging the script I'm writing, I place "echo" commands 
throughout so I can kind of have a trace of the logic as different 
conditions are processed. Normally I just delete these "echo" commands 
after I get the script working.

But this time I want to try something different. I want to 
enable/disable the echo commands in mass. So in the beginning of the 
script I added these 2 lints.

#trace=""  # use to enable trace echo
trace="#"  # use to disable trace echo

In front of each of the echo commands I added this,
  $trace echo "what ever."

When I exec the script I get error message  #: not found

What is happing here? Is the substitution to late?

Is there a way to fix this?

Thanks for your help