[matteason]

It's always "maths" not "math" but we'd always say "the maths says" and I've never questioned it until right now

[timthorn]

It's still singular. Maths is just a contraction of mathematics, but without an apostrophe.

[cpfohl]

Thanks! Now I have more questions, but they're better. This is good progress.

[speerer]

Just like "the science says" (but unlike "the English say" ;) ).