Here are great links to practice your math!!
http://www.ixl.com/math/standards/common-core/grade-5
https://sites.google.com/a/bryantschools.org/math-common-core-resource-site/home-1/5th-grade/5-nbt-2
http://math.com/
5.NBT.7b - Multiplying and Dividing Decimals
5.NBT.2 - Multiplying and Dividing by Powers of 10
Standard: Explain patterns in the number of zeros of the product when multiplying a number by powers of 10, and explain patterns in the placement of the decimal point when a decimal is multiplied or divided by a power of 10. Use whole-number exponents to denote powers of 10.
http://learnzillion.com/lessons?utf8=%E2%9C%93&filters%5Bsubject%5D=math&query=&filters%5Bgrade%5D%5B%5D=5&filters%5Bdomain%5D=NBT%3A+Number+and+Operations+in+Base+Ten&filters%5Bstandard%5D=5.NBT.2%3A+Explain+patterns+in+the+number+of+zer...
http://www.onlinemathlearning.com/multiply-decimals-10.html
http://deannamckinney.weebly.com/ - example webpage
http://learnzillion.com/lessons?utf8=%E2%9C%93&filters%5Bsubject%5D=math&query=&filters%5Bgrade%5D%5B%5D=5&filters%5Bdomain%5D=NBT%3A+Number+and+Operations+in+Base+Ten&filters%5Bstandard%5D=5.NBT.2%3A+Explain+patterns+in+the+number+of+zer...
http://www.onlinemathlearning.com/multiply-decimals-10.html
http://deannamckinney.weebly.com/ - example webpage