Observing Standards-in-Action: Math Classroom Lesson
Produced by Oppix Productions under a contract with MPR Associates from the U.S. Department of Education at the Prince William County Public Schools Education Program, Woodbridge VA
http://www.youtube.com/watch?v=5YjbgFnpltY

Math Instructional Strategies: equivalence of the mathematical expressions of fractions, decimals, and percents
http://www.teachersdomain.org/resource/mistrat.pd.numop1.reinf/
Part of Math Instructional Strategies:Number Operations
http://www.teachersdomain.org/special/mistrat/