8th Grade Performance Task
Contributed by: New York State Education Department (NYSED)
NYS Alternative Assessment in Science Project (1996)
This activity is to used as an assessment after
the students have already been exposed to the use of a dichotomous
key, and therefore know what the term dichotomous refers to, and
how it is used. There are 13 species of Triangulum pictured; it
is suggested that each student identifies any three of the species.
- 1 point is awarded for each correct choice made in the identification
of each species.
- 1 point is awarded for each correct choice or step along the
way.
The scoring of each species should continue until the last
correct choice or step.
The Example given on the Student Answer Sheet (#101) would
be awarded 3 points for a perfect answer. But if the student
had only been able to reach choice 1B before making a mistake,
only 1 point would be awarded.
Since a different number of choices is necessary to identify the
different species, the students may end up with different total
points. Therefore a percent grade should be given.
Total number of points for each species are given below, including
the correct choice for each of the steps.
|
Species Number
|
Species Name
|
Correct Steps
|
Possible Points
|
|
Species # 101
|
T. waveus (10B)
|
(1B-10B)
|
3 points
|
|
Species # 102
|
T. monoflagelleum (6A)
|
(1A-2B-5B-6A)
|
5 points
|
|
Species # 103
|
T. roundflagelleum (12B)
|
(1A-2A-3A-4B-12B)
|
6 points
|
|
Species # 104
|
T. polycilius (9B)
|
(1A-2B-5B-9B)
|
5 points
|
|
Species # 105
|
T. pointiatus (8A)
|
(1A-2A-3B-7B-8A)
|
6 points
|
|
Species # 106
|
T. polyflagelleum (6B)
|
(1A-2B-5A-6B)
|
5 points
|
|
Species # 107
|
T. ventridotteus (11A)
|
(1B-10A-11A)
|
4 points
|
|
Species # 108
|
T. equalius (4A)
|
(1A-2A-3A-4A)
|
5 points
|
|
Species # 109
|
T. biciliatus (9A)
|
(1A-2B-5B-9A)
|
5 points
|
|
Species # 110
|
T. oddcilius (7A)
|
(1A-2A-3B-7A)
|
5 points
|
|
Species # 111
|
T. roundiatus (8B)
|
(1A-2A-3B-7B-8B)
|
6 points
|
|
Species # 112
|
T. pointiflagelleum (12A)
|
(1A-2A-3A-4B-12A)
|
6 points
|
|
Species # 113
|
T. dorsalidotteus (11B)
|
(1B-10A-11B)
|
4 points
|
Total Number of Points - 65 points
Sample Answer Sheet
Choose any of the three species of Triangulum from the species
sheet and key them to their scientific names. Be sure to write in
the numbers of the species that you are trying to identify. In the
proper spaces below write in the number and letter (example #101)
for each of the choices you made as you identified the species.
When you are sure of the species identification, write in the scientific
name in the space provided.
Total actual points - 9
Total possible points - 16
Total actual points / Total possible points X 100 = 56 percent
grade
Scoring Form - Dichotomous Key
Student ID # ____________________
Female / Male (circle one)
|
