This is best illustrated with an example:
Nikkie has 7 children. Sam has no children. Sam thinks Nikkie's kids are cute, but she thinks it would be a lot of work to raise them all together.
Sam: "Your children are so cute, but I think 7 children (1) is or (2) are too many to raise together!"
First of all, I do understand that plural nouns require plural verbs, and yes, "child/children" is a countable noun; thus "Your children are so cute." However, as I think of the meaning of the phrase "7 children" more and more, doesn't it become a sort of measurement like dollars, miles, liters, etc?
Like we say, "1,000,000 dollars is a lot of money," should't we say "7 children is too many to raise together"? Or am I over-analyzing here?