Teacher Pages
Baking Bread Scenario
Directions to the teacher for administering the question are above the question text. The text in the
script font is identical to the text in the student scenario and questions. This text may be read
aloud to the student or the student may read the questions to her/himself.
Directions to the teacher for administering the items are above the question text. The text in the
script font is identical to the text in the student scenario and questions. This text may be read
aloud to the student or the student may read the questions to her/himself.
Teacher Notes for Baking Bread:
The Baking Bread scenario is inclusive of three items that address the following science EALRs: EALR 1:
Systems, EALR 2: Inquiry, and EALR 4: Life Science, LS1. Teachers may select one or all of the items in
the Baking Bread scenario for the student to respond to.
Task
Baking Bread
Question
SYS
Cell Inputs/Outputs
SYS
LS1
Cell Structure & Function
SYS
LS1
New Controlled
Experiment
INQ
APP
LS1
LS2
LS3
INQ
Classroom Activity:
Teachers are encouraged to demonstrate the activity of yeast by following a basic bread recipe.
Completing the experiment is not a requirement for this task, but students may derive a benefit from
doing so. The choice of selecting yeast with the possibility of baking bread is intentionally concrete and
actionable in a school environment. Students and teachers are welcome to conduct a baking bread
investigation while writing the procedure. Please see the final page in this teacher packet for additional
Variations/Extensions/Alternatives for the inquiry portion of this scenario.
Science vocabulary that may require pre-teaching:
Celsius
Cell
Cell membrane
Controlled experiment
Grams (g)
Inputs
Mitochondrion
Milliliters (mL)
Nucleus
Outputs
Temperature
Thermometer
Yeast
Materials:
Required: unlabeled animal cell diagram (available in district-provided resources or online) or an
animal cell model without labels
Optional: Yeast, water, sugar, cans, thermometer, cups, measuring cup or graduated cylinder
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Science LDA: Baking Bread Teacher Pages
Directions: Use the following information to answer questions from the Baking Bread
scenario.
After baking bread at school, Parker and Ollie wondered if changing the amount of sugar
in the recipe affects the yeast. They did the following investigation.
Question: What is the effect of changing the mass of sugar on the temperature of the
yeast mixture?
Prediction: The greater the mass of sugar, the higher the temperature will be.
Materials:
Water
Sugar
Cans
Yeast
Controlled Experiment Setup
Cans with yeast mixture
64 g sugar
32 g sugar
0 g sugar
Table top
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Science LDA: Baking Bread Teacher Pages
Read the data table title, headings and numbers aloud to students.
Procedure:
1. Heat tap water to 45 °C.
2. Pour 125 milliliters of 45 °C water into a can.
3. Add 64 grams (g) sugar to water and stir.
4. Add 32 g yeast to can and stir.
5. Wait five minutes.
6. Record the temperature of the mixture as trial 1 for 64 g of sugar.
7. Repeat steps 2 through 6 for 32 g sugar and 0 grams of sugar
8. Repeat steps 2 through 7 three more times as trials 2, 3, and 4.
9. Calculate and record the average temperature for each amount of sugar.
Data:
Mass of Sugar vs. Temperature of Yeast Mixture
Temperature of Yeast Mixture
(º C)
Mass of Sugar
(grams)
4
Trial 1
Trial 2
Trial 3
Average
64
38
37
36
37
32
39
41
40
40
0
44
45
43
44
Science LDA: Baking Bread Teacher Pages
Baking Bread Item 1: Cell Input / Output Question
Provide students with a simplified cell diagram. Read the item that matches the student packet
(shown below) as needed.
Look at a cell diagram. Describe inputs and outputs of cells like the yeast cell.
In your description, be sure to:
 Identify two inputs of a cell.
 Identify one output of a cell.
One input:
Another input:
One output:
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Science LDA: Baking Bread Teacher Pages
Baking Bread Item 2: Cell Structures and Functions Question
Provide students with a simplified cell diagram. Read the item that matches the student packet
(shown below) as needed.
Look at a cell diagram. Describe the roles of the cell membrane, mitochondrion, and
nucleus in the cell.
Cell membrane:
Mitochondrion:
Nucleus:
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Science LDA: Baking Bread Teacher Pages
Baking Bread Item 3: New Controlled Experiment Question
Read the item that matches the student packet (shown below)as needed.
The student is responsible for generating the steps for the procedure using information previously
presented in the Baking Bread scenario.
Plan a controlled experiment to answer the question in the box. You may use any
materials in your procedure.
Be sure your procedure includes:
 logical steps to do the experiment
 one changed (manipulated) variable
 one measured (responding) variable
 how often measurements should be
taken and recorded
Question: What is the effect of changing the mass of yeast ( 3 , 6 , 9 grams)
on the temperature of the yeast mixture?
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Science LDA: Baking Bread Teacher Pages
Variations/Extensions/Alternatives:
Students are welcome to use text and internet resources (with appropriate accommodations) in
order to respond to the prompts on this LDA.
Below is a table of alternative baking bread lab controlled experiment ideas that may engage
students more than the New Controlled Experiment provided. Teachers are welcome to change the
new investigation question in that item to match the interest level of the student. Students must
write a procedure that matches the investigative question agreed upon by teacher and student.
Alternative Baking Bread Controlled Experiment Ideas
Manipulated Variables
Responding Variables
Temperature of water
Volume of Gas, height of foam formed
Temperature of rising dough
Height or diameter of dough
Acidity of water (pure water, three mixtures
of water and vinegar, and ‘pure’ vinegar)
Volume of gas, height of foam, height of
dough, height of loaf, time to reach 50 °C
Type of wheat flour is ground from, type of
store-bought flour
Height of foam, height of dough, height of
loaf, time to reach 50 °C
A basic white bread recipe was divided by four and the following conversions were used to complete
this experiment in a kitchen, not a lab. Students and/or teachers can use internet resources to find a
similar recipe and use typical kitchen tools for measurements.
2 tablespoons + 2 teaspoons = 32 grams sugar
1 teaspoons = 3.2 grams yeast
½ cup water = 125 milliliters
The learning demonstration is focused on the yeast producing carbon dioxide, not on the
measurement in metric units. Teachers are welcome to use the opportunity to review measurement,
cooking skills and other related concepts, but the purpose of the task is for students to interact with
observable cell functions and inquiry practices.
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Science LDA: Baking Bread Teacher Pages
Scoring Guides for Baking Bread Questions
Baking Bread 1: Cell Inputs/Outputs Rubric
Performance Description
Student responses may provide evidence of understanding of:
 Analyzing a system in terms of subsystems functions as well as inputs and outputs
(EALR 1: Systems)
AND
 Processes within cells (EALR 4: Life Science, LS1)
The response describes inputs and outputs of cells by:
Identifying two inputs of a cell
AND
Identifying one output of a cell.
Examples:
Inputs
Outputs






Food/glucose/sugar/chemical energy
Air/oxygen
Water
Carbon dioxide
Waste
Energy/ATP/heat energy/chemical energy
Baking Bread 2: Cell Structures and Functions Rubric
Performance Description
Student responses may provide evidence of understanding of:
 Analyzing a system in terms of subsystems functions as well as inputs and outputs
(EALR 1: Systems)
AND
 Processes within cells (EALR 4: Life Science, LS1)
The response describes the role of the cell membrane, mitochondrion, and nucleus.
Examples:
Cell membrane
Mitochondrion
Nucleus
9






Keeps things inside the cell/outside the cell
Controls inputs and outputs
Changes food energy to a different kind of energy
Allows the cell to use the energy in food/sugar
Location of DNA/genes/chromosomes
Control center of the cell
Science LDA: Baking Bread Teacher Pages
Baking Bread 3: New Controlled Experiment Procedure Rubric
Performance Description
Student responses may provide evidence of understanding of:
 Planning different kinds of investigations, including field studies, systematic observations, models,
and controlled experiments (EALR 2: Inquiry)
Attributes of a Procedure for a Controlled Experiment
Attribute Name
Description
Changed
(manipulated)
Variable
Only one changed (manipulated) variable (mass of yeast) is identified or implied in
the response.
Measured
(responding)
Variable
The measured (responding) variable (temperature) is identified or implied in the
response.
Record
Measurements
The response states or implies measurements are recorded periodically or gives a
data table, e.g., record the temperature, and write down the mass of yeast.
Trials are
Repeated
More than one trial for each mass of yeast (3 g, 6 g, 9 g) is planned, or implied in a
data table, to measure the measured (responding) variable.
Logical Steps
10
The steps of the procedure are detailed enough to repeat the procedure effectively
(examples of illogical steps: no ending time indicated; states Set up as diagrammed,
but diagram is inadequate; recording vague data or results).
Science LDA: Baking Bread Teacher Pages