The term Maths is an uncountable noun. Am uncountable noun means those things which cannot be counted with numbers. These words don't have a plural form. These words are used with a singular noun. We cannot use words like a, an with these nouns. Examples of some uncountable nouns are
1. Hair- The girl's hair is curly.
2. Water- The taste of this water is sweet.
3. Knowledge - Knowledge is power.
4. Fear- Fear is a negative emotion.
5. Rice- Rice is cooked within half hour.