Subtracting Across Zeros Lesson 4-5 CCSS 4.NBT.4 Literature Link: Panda Math by Ann Nagda * also integrates science with animals

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Warm Up Put these numbers into expanded form. 27,980 137,015 764,003

Today’s Lesson In this lesson, you will subtract numbers with zeros using regrouping.

Think and Write You have learned how to subtract when a number has one zero in it. How do you subtract when there is more than one zero in the greater number?

Subtracting Across Zero When you subtract across zero, it is important to regroup properly. For example, when doing subtraction across zero, you turn the last zero into a ten, and the others into nines because you are taking from them.

Subtracting Across Zeros Place value charts can help when you subtract across zeros. Try 1,400 – 987 using the chart. Have students write the numbers in the box, then use the boxes to help them line up the problem correctly and regroup.

Problem 1 Last weekend, Maya got $100 for her birthday. She spent $54 of it on a new pair of sneakers. How much money does Maya have left?

Problem 2 On Friday, Harry’s Hot Dogs sells 800 hot dogs. On Saturday, they sell 578 hot dogs. How many more hot dogs did they sell on Friday than on Saturday?

Problem 3 Last week, the class solved 1200 math problems. This week, they had a day off from school, so they solved 243 fewer problems. How many problems did they solve this week?

Problem 4 Montclair Middle School has 1,100 students. Garland Middle School has 874 students. What is the difference in student numbers between Montclair Middle School and Garland Middle School?

Problem 5 Sal’s Pizzeria sold 2,000 pizzas last month. Vito’s Pizzeria sold 1,643 pizzas. How many fewer pizzas did Vito’s Pizzeria sell?

Time For Centers Place Value Detectives packet if not complete Game – Race to Zero Game – Quick Questions Meet the Teacher – Want extra help – meet with me! Computer – subtraction - http://www.aaamath.com/grade4.htm

Lesson Wrap Up In this lesson, you learned to subtract numbers that contained zeros and used regrouping. Homework – 4-5 Practice if you understand today’s lesson or 4-5 Reteaching if you would like more practice