Adding Two-Digit Numbers with Regrouping
I.


II.


III.
Purpose:
The purpose of today’s lesson is to review with students the addition of twodigit numbers with regrouping. Today’s lesson begins with a review of
addition of numbers with regrouping then transitions to the addition of two
two-digit numbers. Through this lesson, students will familiarize themselves
with strategies and ways to add two-digit numbers. It is important for students
to be aware of different strategies to add numbers with regrouping. The focus
of any math lesson should not be on finding the correct answer, but focusing
on different ways to solve it.
SOL 2.6: The student, given two whole numbers whose sum is 99 or less, will
o Estimate the sum; and
o Find the sum, using various methods of calculation
Objectives:
Given a graphic organizer, the student will be able to write addition problems
and solve for each sum in the 24 blank spaces with 80% accuracy.
The students will work in partners to be able to complete the Buggy about
Addition math station. Given a graphic organizer, the students will be able to
pick a certain amount of bugs, write the digits in the correct tens and ones
places, and solve each addition problem will 90% accuracy.
Procedure:
a. Introduction
 To introduce the lesson, the teacher will review what the students
know about addition with one two-digit number and a one-digit
number (22+8, 23+4). The teacher will review regrouping with the
students.
 The teacher will circle the digits in the ones place and ask what
needs to be done if that sum is over 10.
 Questions will be asked like:
o In the addition problem, 22+8, what do you need to do to
add these numbers? (Regroup)
o What do I do with 2+8? (Regroup)
 The teacher will write a new addition problem on the board. This
time, the addition problem will be adding two two-digit numbers.
(44+15=?, 45+17=?)
 The teacher will circle the digits in the ones place and ask the class
what they think they should do in order to add the numbers
together. (Regroup)
 The teacher will circle the digits in the tens place (including the
digit that is regrouped) and ask the class to add those digits
together.
 The teacher will ask the students if they want to share any
strategies they have been using to find sums of addition problems.
b. Development
IV.
 Prior to the activity, the teacher will place task cards around the room
for a whole class participation in an addition scoot.
 The teacher will introduce the whole class activity (two-digit addition
scoot) through modeling what is expected of the students. The teacher
will remind the students to move in a quiet manner, working on the
tasks individually.
 The teacher will write on the board the first addition problem in the
scoot.
 The teacher will model how to solve the problem, write the problem
on the graphic organizer, and write the answer on the graphic
organizer.
 The teacher will ask the students to write the addition problem on the
graphic organizer as well as the answer.
 The students will be asked to complete all 24 addition problems placed
around the room.
 After the students complete the scoot, the teacher will introduce a
“Buggy about Addition” station. This is a partner activity. In this
activity, each student will receive a graphic organizer and two tubs of
fake insects. One student will grab a handful of insects and write that
digit in the tens place on the graphic organizer. Then, the student will
grab another handful of insects from the second tub and write that digit
in the ones place. The second partner will grab a handful of insects and
write that digit underneath the digit in the tens place already written.
The student will repeat the same for the digit in the ones place. Both
partners will add up the two-digit numbers. The students will continue
to do this until the graphic organizer is completed.
 For students who struggle: For the students who struggle, the teacher
will allow these students to work together to complete each task card.
Students will receive guidance from the teacher, reminding them how
to regroup the digits. The teacher will allow for student invented
strategies. Additionally, the teacher will further model for the students
how to complete the two-digit addition scoot.
 For students who are advanced: For students who are advanced, they
can move at their own pace to complete the scoot. If these students
finish earlier, the teacher will go over their answers with them, and
assign the students to stations.
c. Summary
 After the students complete the two-digit addition scoot, the teacher will
review some of the questions the students had about certain problems.
 The teacher will ask several students to come to the board to demonstrate
their understanding of certain problems on the scoot activity.
 The teacher will ask the students to turn and talk with one another about
some of the sums they found. The students will talk about different
strategies they used in finding the answers.
 The class will have a whole-class discussion about these strategies.
Materials






V.
VI.
Two-Digit Addition Scoot (Task Cards)
Graphic organizers for the scoot
Pencils
Buggy about Addition math station directions
Containers of fake bugs
Graphic organizer for Buggy about Addition math station
Evaluation Part A:
To assess students’ knowledge on two-digit addition, the teacher will ask
informal questions like, “What do we do if the addition of the digits in the tens
place is over 10?” The teacher will know if the students have grasped this
concept if they say, “regroup”. To further assess the students’ knowledge on
this concept, the teacher will ask the students to complete the addition
problems on the task cards placed around the room. If the students answer all
the problems and get 80% or more accurate, the teacher will know the
students have grasped the concept. Lastly, if the students are able to
participate in the Buggy about Addition math station and place each digit in
the correct ones and tens place (assessing place value concepts as well) with
90% accuracy, the teacher will know the students have a good grasp on twodigit addition.
Evaluation Part B:
My objectives for this lesson were that the students should be able to
complete all 24 two-digit addition math task cards on their graphic organizer, and to write
on their graphic organizer in the Buggy about Addition math station two-digit addition
problems depending on how many fake insects they picked up. The students were to
place the number of insects in the correct tens and ones place on their graphic organizers
to add together. Based on the student samples, some students did meet my objectives.
Some of the learners, especially the ones who struggle, were not able to move at a fast
enough pace to complete all 24 task cards. I was asked by several of these students for
assistance in solving these addition problems. However, the rest of the class seemed to
have a decent grasp on the concept and were able to move at a relatively fast pace to
complete the task cards. Only two students were able to participate in the Buggy about
Addition math station. These students did reach my objectives. I know these students
reached my objectives because they placed the digits in the correct tens and ones places,
and they added the numbers correctly (and regrouped the numbers when necessary).
I believe my lesson did accommodate the needs of all the learners in my
classroom. I allowed the students who struggle with the concept to move at a slower pace
than the rest of the students. I checked in with these students every so often to make sure
they understood how to add the numbers. Additionally, I allowed these students to write
the answer on the blank space instead of the whole addition problem. Some students had
difficulty in writing the complete problem, so I let these students write down the answer.
I was careful not to give the students the correct answer and instead allowed the students
to think on their own how to solve the problem. For the advanced learners, I allowed
them to move at a faster pace to complete the problems. Some of the advanced students
moved onto the station I had planned after they finished, so they had something to do
after the task. I think this activity is a perfect in accommodating the needs of all learners
in the classroom. Many modifications can be made to ensure all students grasp the
concept.
The two-digit addition scoot activity allowed for students to get out of their seats
and move around in the classroom. Movement in the classroom ultimately diminishes the
chances of disruptive behavior because the students are fully engaged in the activity.
Once a task card has been completed, the student is looking for the next card to complete.
Additionally, the activity appeals to all types of learners. Kinesthetic, auditory, and visual
learners are benefiting from this type of lesson. First, the teacher models the lesson and
“thinks aloud” about what she is going to do, and then the students move around the
classroom to pick up task cards and solve the problems. Furthermore, this lesson allowed
for differentiation, and it transitioned nicely into the rotation of math stations. If the
students who struggled were not done with the task cards, they could continue to work on
completing them while the rest of the class worked in stations. There was no pressure on
these students to complete the activity in an allotted amount of time.
Aside from the strengths, there were weaknesses in my lesson. On the day I taught
my lesson, I had to make copies of the materials while the students were in resources.
There were some issues with the copier, and I was not able to get into the classroom to
teach my lesson on time. My cooperating teacher had to begin the lesson by reviewing
some of the addition facts the class had learned. I know now that when I teach lessons, I
will have all my materials ready that day. Additionally, some of the students were not
able to complete all 24 task cards. Reflecting back on the activity, I would have provided
the students who struggled with a graphic organizer that had 12 blank spaces instead of
24. These particular students did not have a chance to participate in math stations (they’re
favorite part of the day). The more advanced students finished the scoot within 15
minutes and were able to participate in math stations.
If I could teach the lesson again, I would have introduced the lesson in a more
engaging way. In every math lesson, it is important that it correlates with the NCTM
standard. I believe my lesson did correlate with most of the standards like
communication, reasoning, and problem solving. However, if I could teach this lesson
again, I would somehow integrate the representation and connections NCTM standards.
Students are more engaged if a lesson touches on their connections to the real world. For
example, I could have introduced a lesson with a word problem about how many students
in second grade had cats and dogs. I would then ask the class to add these numbers
together to find out how many students had these pets. Additionally, I would have used
different representations to strengthen their knowledge on two-digit addition. Base-ten
blocks would have been perfect to use to introduce and review two-digit addition.
Actually regrouping with concrete objects is vitally important for all learners, especially
when the goal is to strengthen their addition skills.