Click on a campaign, then click on an ad group. You should see a Customise Columns button beneath the Summary tab. Click on that, and in the drop-down box you should see a Show Quality Score option. Click on that and all of the ad groups within that particular campaign will display a Quality Score column.
Just be aware that that's only the minimum bid QS, and not the one that's used to determine your advert's position in the search results or the content network. They have similar inputs, so it's probably a decent guide to where you probably are with your QS...