Performance Task: Decimals Gingerbread Baby Hunt by Tabatha Burcher
In this lesson students will review the similarities between fractions and decimals. Students will add and
subtract with decimals. Students must ensure that decimals are lined up when adding and subtracting. Students
must add zeros where necessary.
STANDARDS FOR MATHEMATICAL CONTENT
Perform operations with multi‐digit whole numbers and with decimals to hundredths.
MCC5.NBT.7 Add, subtract, multiply, and divide decimals to hundredths, 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.
STANDARDS FOR MATHEMATICAL PRACTICE
1.
2.
3.
4.
5.
6.
7.
8.
Make sense of problems and persevere in solving them.
Reason abstractly and quantitatively.
Construct viable arguments and critique the reasoning of others.
Model with mathematics.
Use appropriate tools strategically.
Attend to precision.
Look for and make use of structure.
Look for and express regularity in repeated reasoning.
BACKGROUND KNOWLEDGE
Lining up decimals when adding and subtracting is important when finding the sums and differences with
decimals. It is necessary to place zeros in the top number of the problem when subtracting a decimal number
with a hundredths place from a decimal number with a tenths place. The skills developed in this lesson can be
applied to the use of money in real world situations.
COMMON MISCONCEPTIONS

Students bring down the hundredths place when subtracting a decimal number with a hundredths place
from a decimal number with a tenths place, rather than adding a zero after the tenths place in the top
number of the problem. There must be the same place value in both numbers in a subtraction problem.
Example: Incorrect: 5.2
Correct: 5.20
- 3.15
- 3.15
2.15
2.05
ESSENTIAL QUESTIONS








How do we add decimal numbers?
How do we solve problems with decimals?
How do we subtract decimal numbers?
What are the various uses of decimals?
What is a fraction and how can it be represented?
Why does placement or position of a number matter?
Why is place value important when adding whole numbers and decimal numbers?
Why is place value important when subtracting whole numbers and decimal numbers?
MATERIALS








“Gingerbread Friends” by Jan Brett
Answer/Question cards in varying colors
Problem solving sheets in varying colors
Answer keys in varying colors
Gingerbread cookies (or other treat)
Journals
Pencils
Recipe (optional)
GROUPING
Partner/Small Group task
TASK DESCRIPTION, DEVELOPMENT AND DISCUSSION
In this task students will work with decimals, adding and subtracting to find a sum or difference, which will
lead them to their next clue.
COMMENTS
 Before starting this task
o Hide the gingerbread cookies (or treat) somewhere in your classroom.
o Making a “gingerbread house” out of a large cardboard bot to put them in is a fun addition
to the activity.
o Place answer/question cards around the classroom or school. Placing 2-3 of each card in
different locations around the room helps prevent crowding.
o Each level of difficulty should have its own color question/answer cards and matching color
worksheets. The colors allow for differentiation.
 Matching the worksheet color to the card color makes it easy for the students to
know which color to look for.
 Remind students to line up decimals when adding and subtracting decimals.
TASK
 Read “Gingerbread Friends” by Jan Brett to the class. Ask the students to listen for math in the book.
 After reading, ask them what type of math they found in the story. They should answer fractions.
 Ask them what other ways fractions can be represented. When they answer decimals, tell them they are
going on a gingerbread baby hunt and they will be following a trail of decimals to find them.
 Each student will receive a colored worksheet. The colors will allow for the differentiated questions.
The color of the worksheet will match the color of the question cards the students will look for.
 Students will solve the first problem on their own.
 Students will choose a partner with the same color worksheet to work with.
 Students will compare their solution with peer to verify that their answer is correct. They will discuss
and correct any mistakes before moving on to find the next “clue” (which is their answer).
 Once the answer is verified, students will move on to find the card or room number that matches the
answer.
 Continue solving until question #6. Question 6 says “How many kids does it take to find a gingerbread
baby?”
o The answer is the number of kids in the classroom.
o The gingerbread cookies (or other treat) should be found at that answer.
 Once each student has a treat, have them take out their journals and write their own gingerbread man
story incorporating addition and subtraction of decimals in it.

Optional: Pass out copies of the recipe so the students can make the cookies at home.
FORMATIVE ASSESSMENT QUESTIONS






How are decimal numbers and fractions related?
How do you know when you’ve made a mistake?
Why is place value important when adding and subtracting decimal numbers?
What strategy (strategies) are you using to find the next clue? How are your strategies working?
What strategy (strategies) are you using to subtract the decimal numbers? How are your strategies
working?
What strategy (strategies) are you using to add the decimal numbers? How are your strategies working?
DIFFERENTIATION
Extension
 Have students use the worksheet with question # 1: 6.2 + 2.358 =.
o Questions on this sheet are more advanced.
Intervention
 Have students use the worksheet with question # 1: 1.6 + 2.0 =.
o Questions on this sheet are less difficult. Teacher or peer helper can help guide problem solving
as needed.
Additional Activity
 Using the recipe from the “Gingerbread Friends”, make the cookies with the students, incorporating
fractions and measurement into the lesson.
Name __________________________________________
Run, Run as Fast as You Can…
You Can’t Catch Me, I’m the Gingerbread Man!
Directions:
1. Answer the question in box 1.
2. To find the next question, you have to hunt for the gingerbread man card with your answer at the top.
Hint: If you can’t find a gingerbread man card with your answer, go back and re-work the problem.
3. Write down each answer in the boxes below.
4. You will know you’ve found the last answer when you reach the real Gingerbread Man!
Question 1: 42.1 + 9.02 =
Question 2:
Answer 1:
Question 3:
Answer 2:
Question 4:
Answer 3:
Question 5:
Answer 4:
Question 6:
Answer 5:
Answer 6:
Question 1:
42.1 + 9.02 =
Answer 1:
51.12
Question 2:
18.3 – 4.16 =
Answer: Start Question
Answer 1:
14.14
Answer 3:
0.52
Question 3:
1.03 – 0.51 =
Question 4:
0.931 + 0.50 =
Answer 4:
1.431
Answer 5:
7.91
Question 5:
12.31 – 4.4 =
Question 6: How many
kids does it take to
find a gingerbread
baby?
Name __________________________________________
Run, Run as Fast as You Can…
You Can’t Catch Me, I’m the Gingerbread Man!
Directions:
1. Answer the question in box 1.
2. To find the next question, you have to hunt for the gingerbread man card with your answer at the top.
Hint: If you can’t find a gingerbread man card with your answer, go back and re-work the problem.
3. Write down each answer in the boxes below.
4. You will know you’ve found the last answer when you reach the real Gingerbread Man!
Question 1: 1.6 + 2 =
Question 2:
Answer 2:
Answer 1:
Question 3:
Question 4:
Answer 3:
Question 5:
Answer 4:
Question 6:
Answer 5:
Answer 6:
Question 1:
1.6 + 2.0 =
Answer 1:
3.6
Question 2:
3.45 – 3.27 =
Answer: Start Question
Answer 2:
0.18
Answer 3:
4.20
Question 3:
22.37 – 18.17 =
Question 4:
58.067 + 17.86 =
Answer 4:
15.927
Answer 5:
3.5
Question 5:
6 – 2.5 =
Question 6: How many
kids does it take to
find a gingerbread
baby?
Name __________________________________________
Run, Run as Fast as You Can…
You Can’t Catch Me, I’m the Gingerbread Man!
Directions:
1. Answer the question in box 1.
2. To find the next question, you have to hunt for the gingerbread man card with your answer at the top.
Hint: If you can’t find a gingerbread man card with your answer, go back and re-work the problem.
3. Write down each answer in the boxes below.
4. You will know you’ve found the last answer when you reach the real Gingerbread Man!
Question 1: 6.2 + 2.358 =
Question 2:
Answer 2:
Answer 1:
Question 3:
Question 4:
Answer 3:
Question 5:
Answer 4:
Question 6:
Answer 5:
Answer 6:
Question 1:
6.2 + 2.358 =
Answer 1:
8.558
Question 2:
7 – 4.92 =
Answer 1: Start Question
Answer 2:
2.08
Question 3:
8 + 3.67 =
Answer 3:
11.67
Answer 4:
0.4
Answer 5:
5.38
Question 5:
92-86.62 =
Question 6: How many
kids does it take to
find a gingerbread
baby?
Question 4:
9 – 8.6 =
Decimals Gingerbread Baby Hunt
Answer Key:
Intervention
On Level
Extension
Question 1
Answer 1
1.6 + 2.0 =
3.6
42.1 + 9.02 =
51.12
6.2 + 2.358 =
8.558
Question 2
Answer 2
3.45 – 3.27 =
0.18
18.3 – 4.16 =
14.14
7 – 4.92 =
2.08
Question 3
Answer 3
22.37 – 18.17 =
4.20
1.03 – 0.51 =
0.52
8 + 3.67 =
11.67
Question 4
Answer 4
58.067 + 17.86 =
15.927
0.931 + 0.50 =
1.431
9 – 8.6 =
0.4
Question 5
Answer 5
6 – 2.5 =
3.5
12.31 – 4.4 =
7.91
92-86.62 =
5.38
How many kids does it
take to find a
gingerbread baby?
# of kids in room
How many kids does it
take to find a
gingerbread baby?
# of kids in room
How many kids does it
take to find a
gingerbread baby?
# of kids in room
Question 6
Answer 6