Teaching my grandson mathematics in the online regime through Skype, I show him my screen on which a Mathematica notebook is open. I use it to give him tasks by writing simple arithmetical expressions (according to his age) in the Input Cells. Then I show him how to cope with them.
In the course of such sessions I faced one need: I would like to be able to highlight some elements of the expression on the screen. I imagine to operate as follows: I write the expression, then mark its desired element and press a button of a palette with different colors. As a result, the marked element turns into a desired color. Such a palette already exists in the Classroom Assistant but it takes too many clicks to use it. Methodically, it is a disadvantage, since it takes too much time during which the child may get distracted. Such a highlighting should be made quickly. I need a special palette that would hover over the screen and it should take one click to apply.
I tried the following:
CreatePalette[{Button[Style["Red ", White], NotebookWrite[InputNotebook[], Evaluate[Style[NotebookRead[InputNotebook[]], Red]]], Background -> Red], Button[Style["Blue ", White], NotebookWrite[InputNotebook[], Style[NotebookRead[InputNotebook[]], Blue]], Background -> Blue], Button[Style["Green", White], NotebookWrite[InputNotebook[], Style[NotebookRead[InputNotebook[]], Green]], Background -> Green]}] which does not do what I expected.
Any idea, how to achieve that?
