CONCLUSION WRITING
Claim, Evidence and Reasoning
Students should support their own written claims with appropriate justification. Science
education should help prepare students for this complex inquiry practice where students
seek and provide evidence and reasons for ideas or claims (Driver, Newton and
Osborne, 2000). Engaging students in explanation and argumentation can result in
numerous benefits for students. When students develop and provide support for their
claims they develop a better and stronger understanding of the content knowledge
(Zohar and Nemet, 2002).
Research shows when students construct explanations, they actively use the scientific
principles to explain different phenomena, developing a deeper understanding of the
content. Constructing explanations may also help change students’ view of science (Bell
and Linn, 2000). Often students view science as a static set of facts that they need to
memorize. They do not understand that scientists socially construct scientific ideas and
that this science knowledge can change over time. By engaging in this inquiry practice,
students can also improve their ability to justify their own written claims (McNeill et al,
2006).
Remember when providing evidence to support a claim, the evidence must always be:
 Appropriate
 Accurate
 Sufficient
The rubric below should be used when grading lab reports/conclusions to ensure that
students are effectively connecting their claim to their evidence to provide logical
reasons for their conclusions.
Base Explanation Rubric
Component
0
Claim - A conclusion that
answers the original question.
Evidence – Scientific data that
supports the claim. The data
needs to be appropriate and
sufficient to support the claim.
Reasoning – A justification
that links the claim and
evidence. It shows why the
data count as evidence by
using appropriate and
sufficient scientific principles.
Does not make a claim,
or makes an inaccurate
claim.
Does not provide
evidence, or only
provides inappropriate
evidence (evidence that
does not support the
claim).
Does not provide
reasoning, or only
provides reasoning that
does not link evidence to
claim
Level
1
2
Makes an accurate but
incomplete claim.
Makes an accurate and
complete claim.
Provides appropriate but
insufficient evidence to
support claim. May
include some
inappropriate evidence.
Provides appropriate and
sufficient evidence to
support claim.
Provides reasoning that
links the claim and
evidence. Repeats the
evidence and/or includes
some – but not sufficient
– scientific principles.
Provides reasoning that
links evidence to claim.
Includes appropriate and
sufficient scientific
principles.
McNeill, K. L. & Krajcik, J. (2008). Inquiry and scientific explanations: Helping students use
evidence and reasoning. In Luft, J., Bell, R. & Gess-Newsome, J. (Eds.). Science as inquiry in the
secondary setting. (p. 121-134). Arlington, VA: National Science Teachers Association Press.