Does AppleCare+ cover scratches on the Apple Watch?

Apple Care+ will cover 2 instances of accidental damage for a reduced fee. Scratches would fall under that category.

See here for the fees based on version of Apple watch: AppleCare+ - Apple Watch - Apple

Hello,

AppleCare+ for Apple Watch does not protect against normal wear and tear or cosmetic damage that does not affect the functionality of the Apple Watch, including scratches. 

However, it does provide unlimited incidents of accidental damage protection from unexpected and unintentional events such as drops, spills, or cracked screens.

You can get the latest information about AppleCare+ for Apple Watch here: AppleCare Products - Watch - Apple

Note that each incident is subject to a service fee or excess fees. The resource linked above provides an overview of those fees.

Take care!

Scratches on the crystal that affect functioning would most likely be covered. However, I don't think that purely cosmetic scratches on the metal case would be.