Ahava~Love Assembly

Grade 2 Mathematics Week 12 | Teacher Guide

Grade 2 | MATHEMATICS

WEEK 12 • TEACHER GUIDE AND ANSWER KEY • DAYS 56–60

Read each lesson aloud with the child and model the worked example before practice. Do not show this key during practice. Accept oral, drawn or written answers where the child cannot yet write the whole answer. On Day 60, read aloud if needed but give no hints.

Week 12 Student Textbook | Week 12 Practice Workbook | Week 12 Teacher Guide | Week 11 Student Textbook | Grade 2 index

Day 56: Coins and Their Values

Standard: Grade 2 Math Standard 24, 2.M.C.24; Grade 2 Math Standard 24, 2.M.C.24a

Practice figure: Coins drawn to size, printed on the Week 12 Practice Workbook. From left: penny, nickel, dime, quarter. The dime is the smallest coin.

Worked example: How many pennies have the same value as one nickel? Worked answer: 5 pennies.

  1. 25¢.
  2. The dime.
  3. 2 nickels.
  4. 25 pennies.
  5. The size of a coin does not show its value. A nickel is worth 5¢ and a dime is worth 10¢, so the dime is worth more even though it is smaller. Accept any answer that says size does not tell value.

Teaching note: Use real coins whenever possible. The checklist below is for the hands-on sorting task.

Hands-on task observation checklist (Sort and name real coins). Check each item you observe. Four or five items shows the child met the task goal; two or three means repeat the task with support.

  • ☐ Child sorted the coins into four correct piles.
  • ☐ Child named each coin.
  • ☐ Child gave the value of each coin in cents.
  • ☐ Child wrote the value with the cent sign, such as 5¢.
  • ☐ Child counted how many of each coin.

Day 57: Count a Collection of Coins

Standard: Grade 2 Math Standard 24, 2.M.C.24; Grade 2 Math Standard 24, 2.M.C.24b

Practice figure: Coins in Mia’s purse, printed on the Week 12 Practice Workbook. 3 quarters, 2 nickels, 1 penny.

Worked example: Find the value of 1 quarter, 2 dimes and 1 penny. Worked answer: 46¢.

  1. 62¢.
  2. 45¢.
  3. 44¢.
  4. 86¢ (25, 50, 75, 80, 85, 86).
  5. Counting the big coins first lets you count by the bigger numbers and then add the small coins, so it is easier to keep track. Start with the quarter: 25, 35, 45, 55, 65. The value is 65¢. Accept 65¢ with any reason about easier counting.

Teaching note: Line up the coins from greatest to least value before counting. Say each running total aloud.

Day 58: Compare Amounts of Money

Standard: Grade 2 Math Standard 24, 2.M.C.24; Grade 2 Math Standard 24, 2.M.C.24b; Grade 2 Math Standard 24, 2.M.C.24c

Worked example: Which is worth more: 2 dimes or 3 nickels? Worked answer: 2 dimes are worth more. 20¢ is greater than 15¢.

  1. 3 dimes. 3 dimes are 30¢ and 1 quarter is 25¢.
  2. Yes. Both are worth 20¢.
  3. Ben has 75¢ and Ava has 70¢, so Ben has 5¢ more.
  4. 6 dimes (60¢ is greater than 55¢).
  5. A quarter is worth 25¢, but 4 nickels are worth 20¢, so the 1 quarter is worth more. Value depends on which coins they are, not how many. Accept any correct example with values.

Teaching note: Have the child write the value under each group before comparing. Question 3 is a two-step word problem: find each value, then subtract.

Day 59: Make Equal Amounts and Solve Money Problems

Standard: Grade 2 Math Standard 24, 2.M.C.24; Grade 2 Math Standard 24, 2.M.C.24b; Grade 2 Math Standard 24, 2.M.C.24c

Worked example: Show 30¢ in two different ways. Worked answer: 3 dimes, or 1 quarter and 1 nickel.

  1. 2 quarters.
  2. 1 quarter and 2 nickels (25, 30, 35).
  3. 10 dimes.
  4. 15¢ (45 – 30 = 15).
  5. Use the coin worth the most that fits first: 1 quarter makes 25¢, 1 dime makes 35¢, 1 nickel makes 40¢. That is 3 coins. Accept 1 quarter, 1 dime and 1 nickel with a reason.

Teaching note: In the hands-on task, any correct combinations that total 60¢ are acceptable, such as 6 dimes; 2 quarters and 1 dime; 12 nickels.

Day 60: Independent Check: Money

Standard: Grade 2 Math Standard 24, 2.M.C.24; Grade 2 Math Standard 24, 2.M.C.24a; Grade 2 Math Standard 24, 2.M.C.24b; Grade 2 Math Standard 24, 2.M.C.24c

Worked example: Find the value of 1 quarter and 1 nickel. Worked answer: 30¢.

  1. 75¢.
  2. Yes. Both are worth 40¢.
  3. Any two correct ways, such as 2 quarters and 1 nickel, or 5 dimes and 1 nickel, or 11 nickels.
  4. 25¢ (90 – 65 = 25).
  5. No. Her coins are worth 37¢ (25, 35, 36, 37), and 37¢ is less than 40¢. She needs 3¢ more. Accept no with the value 37¢.

Teaching note: Independent check: read aloud if needed, but give no hints. Real coins may be used for counting.

Week 12 Student Textbook | Week 12 Practice Workbook | Week 12 Teacher Guide | Week 11 Student Textbook | Grade 2 index

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