I teach in a high school and I generally have a couple students each semester with 50% extended time.
My solution was:
- Create a group that I called "50% Extended Time".
- Assign the appropriate students to that group.
- Add a group override to each quiz with the new time limit. This way, all I need to do is add a student to a group and it will automatically change their time limits.
- Set the course groups option to No Groups for confidentiality reasons. I have several classes each day that are the same and I like to have them all mixed together in the forums so that they can help each other out and contact each other. For that reason Separate Groups was out. Visible Groups was also out since students could select a drop down list on the Participants panel to see who was in each group.
- Changed the site wide policy so that User Groups was a hidden field in Settings > Site administration > Users > Permissions > User policies. This was also for confidentiality reasons so students couldn't see that another student was in the Extended time group.