We use Scott Forsman and some Investigations for our Math Units of Study.
Units of Study:Place ValueAddition, Subtraction, and MoneyBasic Multiplication and DivisionTime, Data and GraphsMultiDigit Multiplication Area and PerimeterGeometry of Shapes and AnglesMeasurementFractionsVirtual Manipulatives: http://nlvm.usu.edu/en/nav/vlibrary.html
Mulitplication: www.multiplication.com