Mechanism Description Marking Rubrics
Grade
A 80-100%
B 68-79%
C 60-67%
C-/D 50-59%
F below 50%
Introduction
A: Sentences
are 10-12
words inlength.
B: sentences
have too
many clauses
or don’t begin
with the real
subject.
C: Poor word
choice.
D, F: It
doesn’t
conform to
the model.
Part-by-part
description
A: physical
description
helps to
explain
function.
Function is
connected to
location.
B, C: In some
parts the
elements are
out of order.
D, F: Parts are
not in order
and don’t
logically
connect.
Sentence
definition, general
principle of
operation, brief
physical
description and
listing of parts are
perfectly expressed
in the objective
voice. The pattern
of organization is
from the general to
the specific, ending
with a listing of the
parts. An overview
figure is
referenced.
The description of
each part begins by
naming the part.
Each part is
expressed in a
perfectly parallel
format using an
inductive pattern
of organization.
Useful dimensions
and shapes are
ascribed to the
part
The 4 elements
are expressed
reasonably well,
but sentences
may be too long,
and general
principle of
operation begins
with “the user”
and is either too
long or too
short.
The 4 elements
are not
expressed in the
correct order,
and general
principle of
operation is not
clearly
articulated.
Incorrect verb
tenses are used.
Metaphors and
similes detract
from the
precision of
technical
description
There is
unevenness in
the scope of
description from
part to part. The
location of the
part does not
connect to the
following part.
Sometimes an
inductive
pattern is used,
other times a
deductive
pattern is used.
Word choice can
be improved.
There is
inconsistency in
verb tense.
Physical
description is
overemphasized and
general principle
of operation is
not described
well. The
overview figure
isn’t referred to.
Sentences in the
paragraph don’t
cohere.
Document is
incomplete or it
doesn’t conform
to genre
requirements
expressed in the
instructional
checklist. There
are (4\5)
grammatical and
genre errors.
The imperative
voice is used and
the genre is
confused with
instructions.
Parts are not
described well.
Sometimes the
part begins with
naming the part,
other times it
doesn’t. There
are
inconsistencies
in many of the
aspects of part
description.
Patterning and
parallelism are
not discernible.
Accumulates
many of the
errors expressed
in B, C, and D.
There are 5-8
grammatical and
genre errors.
Conclusion
A, B It should
be half the
length of the
introduction
and connect
the part-bypart to the
introduction
tautologically.
It describes how all
the parts fit
together and the
general principle of
operation.
It is missing or
addresses
inappropriate
information,
such as ease of
use and
appearance.
It is either
missing the
general principle
of operation or
doesn’t explain
how the parts fit
together.
Accumulates
many of the
errors expressed
in B, C, and D.
There isn’t
always a
connection from
part to part.
However, there
is still an overall
sense of how
“form and
function”
connect. When
there are
multiple,
identical parts,
the part
description
begins with
“there are”
instead of “Two
mirror image
lever arms”
It is either too
short or too
long.