Summary: Students have an opportunity to work in pairs as they search for the missing addend that will complete a mathematical sentence. Students will demonstrate the ability to change the order of the addends and still produce the same sum.
Main Curriculum Tie: Mathematics Grade 2 Strand: OPERATIONS AND ALGEBRAIC THINKING (2.OA) Standard 2.OA.1 Use addition and subtraction within 100 to solve one and twostep word problems involving situations of adding to, taking from, putting together, taking apart, and comparing with unknowns in all positions, for example, by using drawings and equations with a symbol for the unknown number to represent the problem. Materials:
Additional Resources
Books
 Mission Addition, by Loreen Leedy; ISBN 0823414124
 Quack and Count, by Keith Baker; ISBN 0152050256
 M&M’s Counting Book, by Barbara Barbieri McGrath; ISBN 0881068535
Attachments
Web Sites
Background For Teachers: This activity is designed to give the students an opportunity to
work in pairs as they search for the missing addend that will complete
a mathematical sentence. Students will demonstrate the ability to
change the order of the addends and still produce the same sum. To
insure a smooth transition into the activity, modeling of what the
activity is suppose to look like will have had to be previously taught
and practiced.
Intended Learning Outcomes: 1. Demonstrate a positive learning attitude.
2. Understand and use basic concepts and skills. Instructional Procedures: Invitation to Learn
Pass out a card with an addend on it to each student. The cards
should be numbered 010. Instruct the students that their assignment
is to find someone who has an addend that when added to their
addend will produce the sum of ten. Once they have found the addend
to complete the assignment have them stand next to each other and
hold up their cards. You will collect the cards and make a quick
assessment to see if each pair is correct.
If you have an odd number of students in your class, then one student will be left without a partner. One way to deal with this is let that student be responsible for checking if the pairs are correct. Another way could be to ask the class to figure out a way to incorporate this student into the groups. Maybe they will opt to shuffle the pairs and form one group of 3 to include the student.
Now that each student has a partner we will play a game. Each pair will face each other and put
one hand behind their back. On the teachers mark each student will
show the hand they have been hiding showing a number of fingers
(15). The student who can correctly give the sum of the two hands
quicker wins that round. The students who did not win will take their
seats and the remaining students will pair up with the student closest
to them and play the game again. The game is played until one student
remains. Discuss with the students why for some of them it was easier
than it was for others.
An alternative to this game could be to have the nonwinners partner up and continue playing the game. That way all the nonwinners have a chance to experience being winners and vice versa. You can have the class play a couple of rounds of this. This alternative method has the advantage of leaving the class divided into two equal groups which is what we need for the following activity.
Instructional Procedures
 Students will be separated into two equal groups. Have one
group form a circle, each student should face outward. This
will be the inside circle. Have the second group of students
form a circle around the first circle. Each student should face
inward and line themselves up with a student from the inside
circle. If there is an odd amount of students have two students
from the outside circle pair up.
 Each student from the outside circle should be given a card
from the Missing Addend Sentence Cards. Adapt the cards to fit your students' needs. If your students are ready for it, you might want to give them a sum larger than 12.
 Each student from the inside circle should receive a card from
the Numeral Cards. Adapt the cards to fit your students' needs.
 Tell the students facing each other to check and see if the
numeral the student is holding in the inner circle will make
the math sentence held by the outer circle student true. If the
sentence is true have the pair exit the circle, collect their math
journals, and return to one of their tables as a pair. Together
the pair should record their math sentence in their math journal
and then create and record a math family from the original
sentence.
 After all of the students whose sentences are true have left the
circle have the remaining students in the outer circle rotate to
the right and go through the process found in step 4. Continue
this until all the students have found the math sentence or the
numeral that makes their sentence true.
 All students should now be seated with their partners at a table.
Hand out two dice and the worksheet Missing Addend – Dice to
each pair.
 Explain to the students that the sum they have been working
with for their math family is going to be the sum for all of the
missing addend problems they will be creating. To complete
the worksheet they will first fill in the blank for the sum, and
then they will roll the dice and record the number of dots for
each dice in the space that looks like dice. The sum of the
dice will be recorded on the line above the picture of the two
dice. The students will then solve the addition sentence for the
missing addend. The missing addend will be recorded on the
worksheet in the missing addend symbol.
 For closure to the lesson have a few of the pairs share with the
class how they went about solving the worksheet.
Extensions:
 The number of dice can be increased or decreased.
 Instead of using dice you could use dominoes.
 This activity can be adapted to make a station for a math center.
Family Connections
 Have the students teach their families the different activities
used in class.
 Have family members use household items to create real life
situations with missing addends.
Assessment Plan:
 Observe how the students work together – does one student
dominate the activity?
 Have the students share with you what they are recording in
their math journal.
 Use the Missing Addend –Dice worksheet.
 Have the students verbally explain their thinking process.
Bibliography: Research Basis
Walters, L. S., (2000). Putting Cooperative Learning to the Test. Harvard Education Letter.
May/June 2000. (16).
Cooperative learning in the classroom has a strong research
base. Teachers are moving away from the traditional teaching methods,
rearranging their students into groups where they are encouraged to
talk and share ideas as they shift to accommodate more teamwork
within the classroom. Two essential components need to exist for
cooperative learning to lead to significant gains in achievement. The
first key component promotes interdependence with groups  fostering
the perception that students must work together to accomplish the
goal. The second key component is to hold students individually
accountable for demonstrating their understanding of the material.
Students cannot “hitchhike” within the group.
Lacampagne, Carole, B. (1993). State of the Art: Transforming Ideas for Teaching and Learning
Mathematics. Office of Educational Research and Improvement, July 1993. (114)
This research covers some fundamental shifts for the teaching
and learning of mathematics. For teachers, administrators, and
parents, it presents ten ideas for transforming mathematical teaching.
A major focus is that all students can and must learn mathematics. Mathematics is not linear and hierarchical with teaching rote skills
first, followed by problem solving later; but builds on that students
learn best when they are intellectually challenged so that they are
motivated to fill in mathematical gaps when necessary. Teachers need
to provide stimulating problems and an environment to motivate
mathematical learning.
Author: Utah LessonPlans
Created Date : Jul 09 2007 09:36 AM
