Annotating a worksheet, working with text boxes on non-iPad
When you zoom into a worksheet deliverable and try to place a text box in a particular cell, at the point of click, it repositions the text box to a different place on the worksheet (problem #1)...so you try to move the text box to the correct location and...
(problem #2)... the "+" users normally use to move the text box around allows you to move the box without resizing it when you move it vertically, but if you try to reposition the text box horizontally (by clicking and dragging on the "+" in the top left of the text box) it resizes the text box until you reach the margin of the worksheet. Which means students can't place their text box in the correct cell if they've created it after zooming in.
This problem was noticed when students were on Safari 9.0.1 and didn't occur on an iPad. On Firefox 41.0.2 I wasn't able to zoom in at all to test.