This twenty-four page packet analyzes the second grade common core math standard 2.NBT.6 (Add up to four two-digit numbers using strategies based on place value and properties of operations).
Seven Lessons Breaking Down Four Two-Digit Numbers into Tens and Ones to Add
Four Lessons Rewriting Horizontal Addition of Four Two-Digit Numbers Vertically
Four Lessons on Adding Four Two-Digit Numbers and Comparing and Ordering Sums
Four Lessons Using Word Problems to Add Four Two-Digit Numbers
Thanks bunches, and enjoy! :)