sentences:  Fractions are introduced at age 9/10, decimal numbers and proportions at age 10/11, percentages and rates of interest at age 11/12, algebra at age 12/13.At the secondary level, topics include algebra, geometry, conics, trigonometry, probability, combinatorics and calculus.Descriptive geometry and projective geometry are introduced at age 15/16 and 16/17, respectively.