Before You Begin this Unit…  Unit at a Glance  
In Unit 3 students were encouraged to pay close attention to how numbers were structured, the magnitude of numbers in relationship to other numbers, and how to use the relationships that exist within place value to add and subtract different quantities. Activities like playing close to 7500 along with locating numbers on the 10,000 chart and exploring, selecting anddescribing strategies for addition and subtraction laid a foundation for supporting students through the adding and subtracting of decimals.
The idea in grade 5 is that students are going to “catch on to” addition of decimals much easier than with whole numbers because they have been exploring how the digits move and change when adding units, tens, and hundreds. If students have not been required to pay closer attention to this and only encouraged to compute, they may struggle. If students were not exposed to unit 3 prior to the work of this unit they may struggle with connections as well and you may find that you need to return to whole number ideas to make connections for them. 
Investigation 1: 11 lessons (Including 5A) Investigation 2: 9 lessons (Including 2.5A)


Standards Addressed in the Unit  
Link to CCSS Unpacking Document Updated Sept. '15 (look at pages 3043) 5.NBT.3. Read, write, and compare decimals to thousandths.
5.NBT.4. Use place value understanding to round decimals to any place.
5.NBT.7. Add, subtract, multiply, and divide decimals to hundredths, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. 