When trying to re-create a way to change colors using curves, I noticed you can set keyframes on color changes!
If you want to do this, change the color of the object, right click the color in the material tab, and select "Insert keyframe". It will change to "Replace keyframe" if you already had a keyframe set (see screenshot).
I guess most of you may know this, but I thought I should mention in case there is a person (like me) who did not know about this feature before. It should be useful when trying to make animations of Christmas decorations, changes on colors of objects, etc.