- Calendario
- Capacidad
- Celsius
- Cent
- Centimetre
- Siglo
- Chance
- Círculo, Circunferencia
- Clockwise
- Common denominator
- Common factor
- Common multiple
- Commutative law
- Composite number
- Concave polygon
- Cone
- Convex polygon
- Coordinate plane
- Coordinates
- Counting Numbers
- Cross multiplication, cross products
- Cube
- Cubic centimetre
- Cubic metre
- Cuboid
- Cylinder