Problem: This seems to happen on all SharePoint pages not just LMS, there's only option to minimize or maximize web parts in IE11 when you edit the page.
It is a known SharePoint incompatibility with IE 11
The fix is to run the site in compatibility mode until SharePoint officially supports Internet Explorer 11.
To run in compatibility mode
1. Press ALT + T when viewing your SharePoint page
2. Click Compatibility View Settings in the menu that appears
3. Click Add to add the current SharePoint site to your list of compatibility view pages
4. Click Close
Do this on one course page and it fixes the issue across the LMS.