good

http://www.math-aids.com/Number_Lines/Number_Lines.html

http://www.brighthub.com/education/k-12/topics/math-lessons.aspx

http://www.brighthub.com/education/k-12/articles/33932.aspx

http://www.education.vic.gov.au/studentlearning/teachingresources/maths/mathscontinuum/number/N45003P.htm

http://www.homeschoolmath.net/worksheets/decimal.php

http://www.superteacherworksheets.com/decimals.html

http://www.teach-nology.com/teachers/lesson_plans/math/68/