Our first unit of study is an Investigations Unit called Mathematical Thinking at Grade 2. This unit is all about numbers and reviews important skills like skip counting, and putting numbers in order.  It is important that we learn strategies to add and subtract quickly, especially the factors of 10. 

http://resources.oswego.org/games/mathmagician/cathymath.html

Our second unit of study is an Investigations Unit called Putting Together and Taking Apaart. This unit is all about strategies for solving addition and subtraction problems based on an understanding of numbers, number relationships, and the operations of addition and subtraction. Understanding place value is very important for the students.
http://www.studyzone.org/testprep/math4/c/regrouponestensl.cfm

http://investigations.scottforesman.com/pdfs/parentpage.pdf