You can use the highlighter tool in the top navigation bar to highlight specific text and share it with your students.
Select the text you want to highlight by clicking and dragging your mouse cursor over the selected text you want to highlight.
Click the Highlighter tool and select the color you want to use for your highlighter
Click add highlight. The text you had selected is now highlighted in the color you selected.
To highlight text within the ebook:
You can also select text in the eBook and press the H key to highlight.
To hide all highlights, select hide highlight from the Highlighter tool menu.
All highlighted text references are stored in my notebook.