Tens Multiplication Facts
Students will be able to quickly solve all tens multiplication facts.
- Project the M&M image on the board.
- Ask your students how you can figure out how many M&Ms total you have.
- Give your class a few minutes to think of different strategies.
- React to the answers given by your students. Explain that the fastest way to solve this problem would be to count the number of bags and multiply that number by the number of M&Ms in each bag.
- Ask the class what equation you would use to solve this problem.
- Explain to students that today they'll be learning how to solve multiplication problems that include the number 10.
- Give the class an example of a time that you could use multiplication in a real life scenario. For example: Say you want to go shopping for back to school clothes and want to buy 3 shirts that each cost $10 each. 10 x 3 = 30. Ten times three is the same as three groups of 10.
Explicit Instruction/Teacher modeling(10 minutes)
- Write the following equations on the board: 10 x 3 = 30, 4 x 10 = 40, 10 x 9 = 90, and 6 x 10 = ____.
- Tell the class to share with a partner the patterns they see in these equations. Ask them how they might solve the one with the missing product.
- Let students have about 1 minute to discuss and then have them share their ideas with the class.
- Ask your class if they think it matters if the 10 is first or second in the equation. Have them use 10 x 9 and 9 x 10 as example problems.
- Explain that the answer is the same no matter what order the numbers are in. These are called turn around facts.
- Tell your class that multiplying a one-digit number by 10 is the same as writing the one-digit number and adding a zero. For example, 10 groups of 6 is the same as saying 60 or 10 x 6.
Guided Practice(5 minutes)
- Create more real world problems to solve together with your class. For example: I want 5 new baseball hats. Each hat costs $10. How much money will I spend on new hats? How do you know your answer is correct?
- Demonstrate the answer to this problem in a hands on way using manipulatives.
- Do one more practice problem as a class. Have 7 students stand up and put their hands in the air. Ask your class how many fingers there are among the 7 students. Ask them how they solved the problem.
- Reiterate that 7 x 10 equals 70 because it is the same as saying 10 groups of 7.
Independent working time(15 minutes)
- Pass out a copy of the Tens Multiplication Problems worksheet to each student.
- Walk around the classroom to assist students as they work on the worksheet.
- Enrichment: Students who need an extra challenge may complete the Enrichment worksheet to practice their fluency of tens multiplication facts.
- Support: Students who may be struggling with tens multiplication facts should solve numbers 1-4 on the worksheet. In addition, you may provide math counters or other objects for students to make arrays showing tens multiplication facts for more hands on practice with this concept.
- Give each student 3 sticky notes.
- Have students label their sticky notes 1, 2, and 3.
- Ask students to solve 9 x 10 and 10 x 5 on 1 and 2. They may draw a picture to help them solve it if necessary.
- For number 3 have them explain how they know their answers are correct.
Review and closing(5 minutes)
- Encourage your students to turn and tell their neighbors the product of 11 x 10, and explain how they got their answer.
- Ask the class if anyone can think of other real world scenarios where they would use their tens multiplication facts.