\mathtip{math}{tip}: Use tip (in math mode) as tooltip for math.
Place cursor on math to see tooltip.
$\mathtip{\color{green}{x^2}}{math x*x to explain what this means ...}$
Is colour the best way to show presence of a tooltip?
\texttip{math}{tip}: Use tip (in text mode) as tooltip for math
Place cursor on math to see tooltip.
$\texttip{x^2}{text to explain what this means ...}$
\toggle{math1}{math2}...\endtoggle : Show math1, and when clicked, show math2, and so on. When the last one is clicked, go back to math1.
Exmples:
Click on 1 to see 2, click again to see 3, click again to see 1, ...
$\toggle{1}{2}{3}\endtoggle$
Click on x^2 to see text.
$\toggle{x^2}{this is text in math mode}\endtoggle$
$\toggle{x^2}{\text{this is plain text in math mode}}\endtoggle$