CK-12 Foundation
Ck 12: Arithmetic: Addition of Rational Numbers
[Free Registration/Login may be required to access all resource tools.] Represent sums and differences on a number line and add and subtract rational numbers.
Khan Academy
Khan Academy: Common Denominators
Practice rewriting fractions to have the same denominator. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
CK-12 Foundation
Ck 12: Arithmetic: Decimal Addition
[Free Registration/Login may be required to access all resource tools.] Add and subtract decimals with and without rounding
Better Lesson
Better Lesson: Simplest Form
Given a set of equations students will be able to explain how to reduce fractions to simplest form and determine if the given set of fractions are equivalent.