1. Adding Decimal Numbers UW.5.M.NBT.07Add, subtract, multiply, and divide decimals to hundredths using concrete models or drawing and strategies based on place value, properties ofoperations, and/or the relationship between addition and subtraction; relate the strategyto a written method and explain the reasoning used

2. Essential Questions What is addition? How do you add decimals? What is the thousandth place? How does place value affect value? What about those whole numbers? Where is that hidden decimal?

3. Objective I can add decimals to the thousandths place using models or drawings

4. Let’s Review Think back to last week... What is a decimal number? Talk to your neighbor and see if you can agree on an answer. PART of a WHOLE 15.678 PART WHOLE Separated by a decimal point!!

5. Adding Decimals... Step 1: LINE-UP the decimals so there are right on top of each other. Most Important Step in Adding and Subtracting Decimals.345+.87

6. Adding Decimals... Step 2: Add in any necessary place holding zeros to EVEN THE PLAYING FIELD..345 +.87 0

7. Adding Decimals... Step 3: Add as Usual Step 4: Bring the Decimal STRAIGHT DOWN!!.345 +.87 0 5 1 112

8. Take a Closer Look

9. Partner Practice.37 +.501 =.45 +.1 = *Challenge*.4567 +.21153 =.871.55.66823

10. What About Those Whole Numbers Whole numbers can be a little bit tricky... Remember...EVERY NUMBER HAS A DECIMAL, SOMETIMES IT IS JUST HIDDEN. If you don’t see the decimal in the number, it is hidden at the end! 1234589,999

11. Adding With Whole Numbers... 25 + 1.23 The steps are the same, just don’t forget the hidden decimal. 25 = 25. Line up the decimals Place holding zeros Add as usual Bring the Decimal Straight Down 25. + 1.23 00 26 23

12. Adding with models =12.065

13. Your turn What decimal is represented by each model? Add the two together. What do you get? 3.35 2.52 5.87

14. Guided Practice Let’s try a few on your slates... with drawing pictures and models.356 +.87 = 12 + 3.45 =.567 + 4.98 = 1.226 15.45 5.547 If you have base ten blocks, students can use those to create models of the problems

15. Closure On your slate, create a word problem that requires adding of decimal numbers. Pass your slate to the right and solve your neighbors problem. Pass back and check your neighbors work. Repeat todays objective

16. Independent Practice 3.45 +.568 57.89 +.00567.0045 + 2.09 306.09 +.75 12.009 + 7.90 1.00005 +.998.00902 + 2.05 3.0079 + 2.98