All you need to teach about functions and relations including one-to-one and many-to-one functions, relations, vertical and horizontal line test, domain and implied domain, range; piecewise functions and continuity, inverse, composite, reciprocal functions. Real life applications and modelling with functions. GDC screens and hints. Absolute value. Even and odd functions and more. Examples, investigations, additional exercises. Suitable for IB Mathematics or any other Algebra and Functions courses.