Continuing Rounding Numbers Math Workshop 3 rd Period January 24, 2011

Agenda Bell Ringer – 10 Rounding Questions Review homework and graphs (grades) Continuing Rounding Numbers (PowerPoint) Class Work (Worksheets on Rounding Numbers) Independent/Pairs Homework – Due Monday, January 23

Place Values and Rounding For example: Round to the nearest 100 (hundred) 231 What number is in the hundreds place? Underline that number 231 Place a dot below the number to the right of the underlined number 231 Does a three mean to round up or stay the same? 0 – 4 = stay on the floor and 5 – 9 = climb the vine Round down (stay the same) Add zeros behind the number you underlined 200

Steps to a Successful Rounding 1. What are we rounding? 2. Underline the number we are rounding 3. Place a dot below the number to the right of the underlined number 4. Does the dotted number tell us to round up or stay the same? stay on the floor (SAME) climb the vine (UP) 6. Round the Underlined Number Up keep the SAME 7. Add zeros behind the number you underlined

A Rhyme to Remember… 0 through 4 stay on the floor 5 through 9 climb the vine

Examples: Round 18 to the nearest 10s (tens) One is in the tens place. Pick the only two numbers it can be… 10 or What does the 8 tell me? 5 – 9 Climb the Vine (UP) One number higher than 1 is… 2 Add zeros behind the underlined number 20

Examples: Round 13 to the nearest 10s (tens) One is in the tens place. Pick the only two numbers it can be… 10 or What does the 3 tell me? 0 – 4 Stay on the Floor (SAME) 1 can stay the same Add zeros behind the underlined number 10

Examples: Round 370 to the nearest 100s (hundreds) Three is in the hundreds place. Pick the only two numbers it can be… 300 or What does the 7 tell me? 5 – 9 Climb the Vine (UP) One number higher than 3 is… 4 Add zeros behind the underlined number 400

Examples: Round 105 to the nearest 100s (hundreds) One is in the hundreds place. Pick the only two numbers it can be… 100 or What does the 0 tell me? 0 – 4 Stay on the Floor (SAME) 1 can stay the same Add zeros behind the underlined number 100

Example: Round 257 to the nearest 10s (tens) Two is in the hundreds place. Pick the only two numbers it can be… 200 or What does the 7 tell me? 5 – 9 Climb the Vine (UP) One number higher than 5 is… 6 Add zeros behind the underlined number 260

Class Work Students will work on worksheets at their pace on Rounding Numbers. You may work independently or with pairs. Raise your hand if you have a question.

Homework Students will be given 10 practice problems on rounding to complete by Wednesday’s class.