Note that Example 2 (Baby steps) in Customize the Office Ribbon (It doesn't take rocket science) by Greg Maxey gives an example on removing a group from a Tab as well as rewriting one. If you have a template with this, loaded as a Global Template, it will change the Ribbon.

Are you a teacher trying to keep students from utilizing the spelling and grammar check tools in Word?

Removing the Editor from the Home tab, though, does not block use of the spelling and grammar. It merely hides it a bit.