Khan Academy
Khan Academy: Find Perimeter by Counting Unit Squares
Calculate the perimeter of a rectangle from its side lengths. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Illustrative Mathematics
Illustrative Mathematics: 6.g Painting a Barn
This task asks students to determine the area of the exterior walls of a barn and to calculate how many gallons of paint would be needed to cover them, as well as the cost of the paint. Aligns with 6.G.A and 6.RP.A.3.
Texas A&M University
Wtamu Virtual Math Lab: Intermediate Algebra
This site is a tutorial for students in algebra 2 or for those who need a refresher. The site has explanations, definitions, examples, practice problems and practice tests are found covering topics such as linear equations, graphing,...