In regards to the rest of the posts stating its because of lack of functionality rather than functionality, why not design and write tests (math tests specifically) so that no calculator is required. Core Calculus, Stats, etc. concepts are testable without exact numerical precision. Substitute variables if needed, or have end results allowable in non reduced formats.
I guess the only thing good in it is that parents (and maybe even grandparents?) can pass them on to younger generation like a family heirloom, and child won't even get anything outdated.
