"There is something that doubts me"

At the end of class one day, after I’d answered some questions about recognizing acute angles and isosceles triangles:

Sankung: Miss Jallow, there is something that doubts me. In every other class the teachers have been able to give me a definition but never has a teacher given me a definition for maths. What is the definition of maths?
[the rest of the class looks up attentively]
Me: Never?
Sankung: Never.
Me: Hmm…
[and then I stumble through a definition that discusses geometry, algebra and statistics until I am forced to admit…]
Me: But a definition for all of maths? I do not know.
Isatou M. saves me: Maths is the key to life!
Me: It’s true, maths is the key to life. Even if you want to go to a naming ceremony and you have to buy asobi you must use maths. How much fabric do you need? How much will it cost?
Therese jumps to her feet!
Therese: Yes! Even if you are walking you are using maths. [she takes a few steps] How far are you going? Me: Even if you are buying a bean sandwich!
Therese: Yes, even beans! That is all he [she points to Sankung] is thinking about, ‘should I buy half bread or full?’
Then Ansumana presents an acrostic poem definition of maths, in which M stands for “movement,” but I forget the rest, unfortunately.

However, the definition of maths question continued to bother me. After I went home, I referred to the How and Why Wonder Book of MATHEMATICS but none of the questions listed in the table of contents (“what is the language of multiplication?” “how did the Phoenicians navigate?”) includes “what is mathematics, anyway?” The Introduction even claims the book gives “an over-all view of what mathematics is” but it’s left to readers to figure out how prime numbers, polygons, graphs, and the sexigesimal system are related.