Students will be able to multiply whole numbers of up to four digits by one-digit and two-digit whole numbers, using strategies based on place value.
- Begin this lesson by reviewing place value. Write a five-digit number on the board. Have students come to the board and identify each number's place value.
- Tell students that today they are going to use what they know about place values to help them calculate multi-digit numbers.
- Write a two-digit by one-digit multiplication problem on the board.
- Have students raise their hands and work on solving the problems to show you if they have previous experience with multiplying multi-digit numbers like the one on the board.
- Explain to them that it is very doable as long as they know the value of the two single numbers, place value, and a strategy called regrouping.
Explicit Instruction/Teacher Modeling(25 minutes)
- Remind students of basic multiplication facts by using Multiply! as a quick review.
- Review the answers by using the answer key.
- Offer students suggestions for this quick assignment by reviewing the patterns found in each row.
- Use the table to work problems in which double digit numbers are multiplied by single digit numbers using problems from the Multiplication with Regrouping or Mammoth Multiplication Problems worksheets.
- Next use problems from the Double Digit Multiplication worksheet to use place value when multiplying multi-digit numbers by two-digit numbers.
Guided Practice/Interactive Modeling(20 minutes)
- Have students find a partner.
- Pass out the Math-Go-Round (Hard) game and scratch paper for completing their calculations.
- Read the instructions for the game to students. Set a time limit for each calculation or for the entire game if you would like.
- Ask students if they have questions.
- Have students work in pairs to complete the calculations.
- Allow the last 2-4 minutes to discuss challenges.
Independent Working Time(20 minutes)
- Pass out the Math-Go-Round (Expert) game and scratch paper for completing their calculations to students.
- Tell students that they will work alone to complete the game board.
- Make this a timed assignment if you would like.
- Remind students to use place value when calculating multi-digit numbers by two-digit numbers.
- If students get stuck, advise them to go to the next calculation.
- Allow time to review the challenging problems (as determined by the students) and answers after this assignment.
- Enrichment: Advanced students could create a children’s book with step-by-step instructions for multiplying multi-digit numbers by one and two-digit numbers. They could also complete the Multiplying Multi-Digit Numbers worksheet which requires them to multiply several six-digit numbers by two-digit numbers and even multiply by three-digit numbers.
- Support: Students who need extra support could create their own more simplistic problems and answer them.
- Use the Multiplication Mischief worksheet to assess students' understanding of the lesson.
- Remind students that they must use place value to answer each question.
Review and Closing(5 minutes)
- Review place value and the multiplication chart.
- Write an equation on the board and have students work the problem out with you on the whiteboard.
- Remind students that it is important for them to understand multiplication and place value.