TY - BOOK AU - Heddens, James W. TI - Today´s Mathematics : Concepts, Methods, and Classroom Activities SN - 978-0470-28690-6 U1 - 510 PY - 2009/// CY - Estados Unidos PB - Wiley KW - MATHEMATICS N1 - Learning mathematics - Assessing mathematics - Technology in K-8 Mathematics - Addition and subtraction of whole numbers - Number theory and number systems - Rational numberss expressed as fractions: operations - Algebraic reasoning: Generalizing patterns and relationships ER -