For Mac OS users, there is a system setting that may not allow you to tab onto several types of elements in a web page. To change this setting:
Early Release Schedule
1st Period - 8:00-8:22
2nd Period - 8:27-8:49
3rd Period - 8:54-9:16
4th Period - 9:21-9:43
6th Period - 9:48-10:10
7th Period- 10:15-10:37
8th Period - 10:42-11:04
7/8 Lunch - 11:09-11:32
5th Period - 11:37-12:00