 Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum          A B C  Notes for Session 8, Part B Note 4 Many people who have trouble with fractions and computations with fractions do not have a mental image of what a fraction represents, which makes it very difficult to do computations. This section gives a concrete representation of the fractions and helps you understand why the shortcuts for computations work. Note 5 To learn more about different meaning of operations, go to Session 4, Part A. Note 6 The Cuisenaire Rods model illustrates why the algorithms for adding and subtracting fractions work -- namely, that you cannot add the fractions until they are expressed in the same units. It also shows why the alternative algorithm for dividing fractions (finding a common denominator and then dividing the numerators) works. It does not, however, illustrate why the multiplication algorithm (multiplying the numerators and multiplying the denominators) works.   