Here is a set of 10 worksheets on adding decimals that are tied to the common core standards for 5th and 6th grade. Great practice in adding decimals and also great practice in problem solving. These are sure to keep the kiddos busy trying to figure out which decimals add to 100. They will be getting plenty of practice here. Print and you are ready to go. Great to use as a whole class activity or as a math center activity. Answer key included.