Is there a plugin compatible with BoldGrid to add an expand/collapse function to a div?

You can use the following code for creating expanding or collapsing divs:

Bootstrap (3.3.7) – Collapse code

I saw the code work, so Bootstrap is being loaded with the BoldGrid.  I tested the code by doing the following:

1. Opened post to edit
2. Clicked on block and then added a section.
3. I then typed in a quick marker in the Visual editor to let me know where I wanted the code to be set.
4. Next, I went to the TEXT editor tab.
5. I looked for the text I added.  I highlighted the code and then pasted the Collapse code provided by Bootstrap.
6. You will need to edit the code in order add your own content.

Once I had the code in place, I looked at it in the Visual tab.  Each of the collapsed sections are OPEN in the Visual editor.  You can preview the page and then you can click on the links for collapsing or expanding the sections.  I plan to write a tutorial on this shortly, but you have the basic steps.

I hope this helps!