Proper English?

[Fred_Frederickus]

So, we've been having this discussion for decades about some English. Which one of the two is correct?

There were an unbelievable amount of presents dropped.
There was an unbelievable amount of presents dropped.

I'd say the second sentence is correct, because the "an unbelievable amount of presents" is the subject. An amount is singular so it's got to be was, but some people disagree.

What do you think is correct and please tell us why?