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:
SGMS Schedule
https://drive.google.com/file/d/0B6YtlN12Bgiyc1ZNTXZ0SjFnUlNEeHF6S19BRVBGRWEtSUlz/view?usp=sharing