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:
5TH GRADE - 8:05 3RD GRADE - 9:00 4TH GRADE & PK - 10:05 2ND GRADE - 12:15 1ST GRADE & PK - 1:10 KINDERGARTEN - 2:05