A family of Microsoft presentation graphics products that offer tools for creating presentations and adding graphic effects like multimedia objects and special effects with text.
This isn't an everyday request here but it does come up from time to time.
Please use the Send Feedback feature in PowerPoint to send a feature request to the PowerPoint programmers.
Meanwhile there's a workaround that might do for you:
Add a text box on the slide itself, type the text you want to have the link apply to and then apply the link to the text (select all the text, press Ctrl+K is the short cut).
Then select the text box itself (not the text within .. click inside the text then press ESC, then Ctrl+C).
Switch to the Notes Page view and Ctrl+V to paste the text box into the notes page as an independent shape rather than as part of the notes text.
It'll now work as a link in Note Page view. If there are many links in each page's worth of notes, it'll be easier for the students to follow if you make them more like footnotes, superscripted numbers in the notes text, matching superscript #s in the text box with the links.