Hi Hannah,
No, we don't have anything pre-built that does that. We've built a number of custom solutions before where one or more people can authorize a change before it goes live, so custom building something is an option, but there's no built in functionality that provides that feature.
One low-cost way that you could do something like that would be to have another section called "Pending Approval" where you posted content that needed to be approved, and then have the editors copy and paste it over into the actual section once it was approved. Or another way to do the same thing is just to add another set of fields to the section you're working with for "pending updates" and let people review them in the CMS before copying them over.
Hope that helps.
Dave Edis - Senior Developer
interactivetools.com