2. Estimating Sums and Differences By Mr. Bales

3. Objective  By the end of the lesson, you will be able to estimate sum and differences of numbers.  Standard 4NS3.1 - Demonstrate an understanding of, and the ability to use, standard algorithms for addition and subtraction of multidigit numbers.

4. Introduce  Look at this number: 2,362  What is this number rounded to the nearest hundred?  Don’t remember – let’s listen to the Rounding Rap  Let’s play “Eliminator” but we’ll round this time

5. Teach  In my left pocket, I have my entire paycheck - $1.29.  In my right pocket, I have $0.74.  I want to know about how much money I have. What could I do to estimate about how much money I have?  What could $1.29 be rounded to?  What could $0.79 be rounded to?  About how much money is $1.29 + $0.79?

6. Let’s Watch Mr. Hardesty!! Mr. Hardesty

7. Time for Robo Works!! Robo Works!!

8. Bales Bucks  Estimate. Round to the place value shown.  312 + 27; tens  1,561 + 305; hundreds  $21.75 + $73.14; tens  383 – 122; hundreds  $74.50 - $52.74; tens  37,215 – 6,792; thousands  $20,425 + $47,236; thousands

9. Assignment  Page 60 - #’s 9 – 20  Get them all correct – 2 Bales Bucks!!