Within this product, you will find the items I use in my own classroom to help students learn to add three addends on a number line. In this activity, students will roll a number cube three times to find a number sentence. They will use a number line to show how they solve.
Included in this product download:
-Suggested lesson outline
-Addend vs. sum example cards for labeling
-Number line cars for class practice opportunities
-Vocabulary cards: addend, sum, efficient, Count on, number line, adding on a number line, efficient adding on a number line
-Student activity sheets (2 options)
-Number card sets, in case you don’t have number cubes
For a short time, I focus on a variety of ways to solve number sentences with three addends in order to build a foundation for work with three addends for other purposes:
CCSS.Math.Content.1.OA.A.2Solve word problems that call for addition of three whole numbers whose sum is less than or equal to 20, e.g., by using objects, drawings, and equations…
CCSS.Math.Content.1.OA.B.3Apply properties of operations as strategies to add and subtract.2 Examples: If 8 + 3 = 11 is known, then 3 + 8 = 11 is also known. (Commutative property of addition.) To add 2 + 6 + 4, the second two numbers can be added to make a ten, so 2 + 6 + 4 = 2 + 10 = 12. (Associative property of addition.)
And for developing stronger addition skills:
CCSS.Math.Content.1.OA.C.6Add 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).
And finally, to build a solid understanding of the vocabulary ‘sum’ and ‘addend’ for later teaching on the topic of ‘missing sum’ and ‘missing addend:’
CCSS.Math.Content.1.OA.D.8Determine the unknown whole number in an addition or subtraction equation relating three whole numbers. For example, determine the unknown number that makes the equation true in each of the equations 8 + ? = 11, 5 = _ - 3, 6 + 6 = _.
If you are interested in the sequence of lessons that helped to build up to this particular lesson, or lessons that follow and lead to the CCSS listed above please see my store or contact me.
However you use this ‘Solving for THREE addends on the number line’ Lesson/Activity Set, I genuinely hope that you find these materials helpful in your classroom!
Happy teaching & happy learning.