That does seem weird 
You could change the relevant permission level in the %permissionLevels hash in global.conf (or simple.conf) to "student", but that would affect every set and every problem on your server (global.conf) or in your course (simple.conf), and is probably not what you want.
There are two other options I can think of:
a) Embed the answer in a hint block. E.g.
BEGIN_HINT
This is the answer!
END_HINT
the students will have access to the hint after 3 attempts by default. (I think it's 3)
b) Use the new PeriodicRerandomization.pl macro written by Paul Pearson.
http://webwork.maa.org/moodle/mod/forum/discuss.php?d=2572
But this has the effect of changing the student's problem after the answer to the student's current version is shown.
Hope this helps!
Jason
You could change the relevant permission level in the %permissionLevels hash in global.conf (or simple.conf) to "student", but that would affect every set and every problem on your server (global.conf) or in your course (simple.conf), and is probably not what you want.
There are two other options I can think of:
a) Embed the answer in a hint block. E.g.
BEGIN_HINT
This is the answer!
END_HINT
the students will have access to the hint after 3 attempts by default. (I think it's 3)
b) Use the new PeriodicRerandomization.pl macro written by Paul Pearson.
http://webwork.maa.org/moodle/mod/forum/discuss.php?d=2572
But this has the effect of changing the student's problem after the answer to the student's current version is shown.
Hope this helps!
Jason
The following worked for me:
Under Course Configuration, click on Permissions at the top, then change Allowed to see the correct answers before the answer date to student. When I logged in as a student I was able to Show Correct Answers while the set was still open.
As Jason says, this will affect all sets in your course.
BTW don't edit simple.conf. If you want to edit config options for a specific course from the command line, do it in course.conf.
simple.conf gets overwritten every time you make a configuration change using the web interface, so you shouldn't manually edit this file.
Danny
This is a good solution. It's easy enough to turn it on and off depending on what your intentions are for the current assignment. Thanks a lot.