Chapter 4

Subtraction Facts to 10

1st Grade: Chapter 4 Outline

Week 8 - Week 10

Essential Questions:

    • How do I know if 5+3=10-2?
    • What is the meaning of the equal sign in a number sentence?
    • How do I know if an equation involving addition and subtraction is true or false?
    • How do I write a fact family from a given number sentence?
    • What strategies can I use to make addition or subtraction easier?
    • How can drawing a picture and writing a number sentence help you solve subtraction problems?
    • How can counting on or counting back help me to subtract?

Content:

Students will know and understand:

    • Take away to subtract.
    • Count on to subtract.
    • Count back to subtract.
    • Use number bonds to subtract.
    • Write and solve subtraction sentences.
    • Solve real-world word problems.
    • Relationship between addition and subtraction.

Skills:

Students Will:

    • Determine if an equation is true or false
    • Determine if both sides of an equation balance
    • Use mathematical tools and representations
    • Use properties and strategies to solve subtraction problems within 10.
    • Use various strategies to solve subtraction problems.

Assessment

Chapter 4 Assessment: Subtraction Facts to 10

Formative Test: Common

Upon completion of Unit 4:

  • 1.OA.A.1. Use addition and subtraction within 20 to solve word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem.
  • 1.OA.B.4. Understand subtraction as an unknown-addend problem.
  • 1.OA.C.5. Relate counting to addition and subtraction (e.g., by counting on 2 to add 2).
  • 1.OA.C.6. Add and subtract within 20, demonstrating fluency for addition and subtraction within 10. Use strategies such as counting on; making ten (e.g., 8 + 6 = 8 + 2 + 4 = 10 + 4 = 14); decomposing a number leading to a ten (e.g., 13 – 4 = 13 – 3 – 1 = 10 – 1 = 9); using the relationship between addition and subtraction (e.g., knowing that 8 + 4 = 12, one knows 12 – 8 = 4); and creating equivalent but easier or known sums (e.g., adding 6 + 7 by creating the known equivalent 6 + 6 + 1 = 12 + 1 = 13).
  • 1.OA.D.7. Understand the meaning of the equal sign, and determine if equations involving addition and subtraction are true or false. For example, which of the following equations are true and which are false? 6 = 6, 7 = 8 – 1, 5 + 2 = 2 + 5, 4 + 1 = 5 + 2.
  • 1.OA.D.8. Determine the unknown whole number in an addition or subtraction equation relating to three whole numbers.
  • 1.NBT.A.1. Count to 120, starting at any number less than 120. In this range, read and write numerals and represent a number of objects with a written numeral.
  • 1.NBT.C.4. Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.
  • MP.1. Make sense of problems and persevere in solving them.
  • MP.2. Reason abstractly and quantitatively.
  • MP.3. Construct viable arguments and critique the reasoning of others.
  • MP.4. Model with mathematics.
  • MP.5. Use appropriate tools strategically.
  • MP.6. Attend to precision.
  • MP.7. Look for and make use of structure.
  • MP.8. Look for and express regularity in repeated reasoning.