Claim, Evidence, &
Reasoning — Writing
Scientific Conclusions
ELIZABETH GORDON, NBCT
MYP & IB BIOLOGY INSTRUCTOR
Me…
& You…
Middle School?
Biology?
Chemistry?
High School?
Physics?
Life Science?
My Dad’s a Space Alien
I have evidence that proves
my Dad’s a space alien.
He speaks a weird language.
He drinks green stuff.
He says he’s from Albuquerque (I’m not
buying it).
I mean, just look at him.
And one more thing. He has a space
ship.
The evidence doesn’t lie.
My dad’s an alien.
What is a Scientific
Explanation?
Claim
Evidence
Reasoning
www.edutopia.org/blog/science-inquiry-claim-evidence-reasoning-eric-brunsell
Question: What do you want to know?
Claim:
• A statement that answers your question
Evidence for your claim:
• Scientific data that support the claim
• Data need to be appropriate
• Data need to be sufficient (more data = strength!)
Reasoning (how your evidence justifies your claim):
• Based on scientific principles
• Each piece of evidence may have a different
justification for why it supports the claim
• Usually several sentences; useful prompts include “if,
then”, “therefore”, “because”, “since”
Adapted from : McNeill, K.L. and J.J. Krajcik. 2012. Supporting Grade 5–8 Students in Constructing Explanations in Science:
The Claim, Evidence, and Reasoning Framework for Talk and Writing. Chapter 2, p. 35.
CER- The Foundation
https://www.nsta.org
McNeill, K.L. and J.J. Krajcik. 2012. Supporting
Grade 5–8 Students in Constructing
Explanations in Science: The Claim, Evidence,
and Reasoning Framework for Talk and Writing.
CER- The Foundation
“…In the debate classroom
students do more than just
memorize and spit back
facts, they own and direct
their learning…”
http://budl.org/about/
I have evidence that proves
my Dad’s a space alien.
He speaks a weird language.
He drinks green stuff.
He says he’s from Albuquerque (I’m not
buying it).
I mean, just look at him.
And one more thing. He has a space
ship.
The evidence doesn’t lie.
My dad’s an alien.
Writing an Explanation
Question: …
Claim:
Evidence:
…
Reasoning:
…
Writing an Explanation
Question: Who is my Dad?
Claim:
My Dad’s a space alien
Evidence:
•
•
•
•
•
He speaks a weird language
He’s from Albuquerque
He drinks green liquids
He dresses funny
He drives a spaceship
Reasoning:
The evidence doesn’t lie...
Writing an Explanation
Question: Who is my Dad?
Claim:
My Dad’s a space alien
Evidence:
Reasoning:
• He speaks a weird
language
• Aliens are not from Earth so they
have their own language
• He’s from Albuquerque
• Some people believe that aliens
have landed in NM
• He drinks green liquids
• Which is why many aliens are seen
with green skin
• He dresses funny
• Aliens wear space suits for
protection
• He drives a spaceship
• Aliens use spaceships to travel
NGSS- Scientific & Engineering
Practices
1. Asking questions and defining problems
2. Developing and using models
3. Planning and carrying out investigations
4. Analyzing and interpreting data
5. Using mathematical and computational thinking
6. Constructing explanations and designing
solutions
7. Engaging in argument from evidence
8. Obtaining, evaluating, and communicating
information
NGSS Practices relevant to C-E-R
1. Asking questions and defining problems
2. Developing and using models
3. Planning and carrying out investigations
4. Analyzing and interpreting data
5. Using mathematical and computational thinking
6. Constructing explanations and designing
solutions
7. Engaging in argument from evidence
8. Obtaining, evaluating, and communicating
information
NGSS Practices relevant to C-E-R
1. Asking questions and defining problems
2. Developing and using models
3. Planning and carrying out investigations
4. Analyzing and interpreting data
5. Using mathematical and computational thinking
6. Constructing explanations and designing
solutions
7. Engaging in argument from evidence
8. Obtaining, evaluating, and communicating
information
CER- First Try

With 2-3 people sitting near you, construct an
argument around the topic you are given
 You
will have 10 mins total to write your
argument
 You
may use your cell phones to search for
“data”; data must be numerical
 Remember
reasoning!
 Write
to link your data to your claim with
out your argument using C-E-R with the
materials provided
CER- My Students 1st Try
Using C-E-R
in the Classroom

Scaffold! Help your students build their skills
 Introduce
C-E-R using a non-science example
(most successful NFL Quarterback, musical artist,
etc.)
 Include
analysis
the C-E-R graphic organizer in lab
 Have
students work in pairs/groups
 Have
students work independently
Using C-E-R
in the Classroom

Model
 Use
“Think Aloud” to mentally review C-E-R
 Always
ask students to articulate evidence
and/or reasoning when they are answering
questions
 Encourage
students to challenge EACH OTHER in
small groups
Using C-E-R
in the Classroom

Challenge
 Have
students evaluate each other’s scientific
arguments and provide feedback
 Allow
students to revisit their original argument
and modify/improve it
 Ask
students to add rebuttal to further strengthen
their argument students (C-E-R-R)
Using C-E-R
in the Classroom

Remember…

C-E-R is not appropriate for every science learning
task. It’s only appropriate when students make
sense of data using scientific principles.
 “Write
a scientific explanation about 3 everyday
examples of chemical reactions” is NOT a good
use of C-E-R
Using C-E-R
in YOUR Classroom
Take a moment and think about your current course
and instructional activities.

Where can you easily incorporate C-E-R? Think of
a specific task/unit and a question that students
can answer using C-E-R.

In what ways could you modify other instructional
tasks to incorporate C-E-R?
C-E-R in My Classroom
What kind of inheritance is this?
C-E-R in My Classroom
Which item is the healthier choice?
Breakfast
Item A
Breakfast
Item B
C-E-R in My Classroom
What kind of cell is this?
10 µm
Thoughts? Questions?
eagordon@bcps.k12.md.us