8th Grade Performance Task
Contributed by: Third International Math and Science Study (TIMSS)
Criteria for Fully-Correct Response
Item 1 - Record rubber band length as rings
are added. Response is scored for both the quality of the
presentation and the quality of data collection.
Item 2 - Graph results (graph or bar
chart). i) Axes correctly scaled. ii) Axes correctly labeled,
including units where appropriate. iii) Measurements recorded
in graph are consistent with data table. iv) Graph reflects trend
in data.
Total Possible Points: 3
Item 3 - Calculate increase in length of rubber
band when rings are added. i) Records amounts consistent
with data in table, graph or bar chart. ii) Calculates increase
correctly
Total Possible Points: 2
Item 4 - Describe how rubber band length changes
as more rings are added. i) Description corresponds to data
in table or graph. ii) Identifies trend in data. Trend may show
that rubber band length increases consistently with each added
ring; initially rubber band length increases consistently, then
begins to level off; increases become larger or erractic with
more rings (elastic limit of band exceeded); no change in length
occurs (rubber band too strong for weights, per administrator
notes).
Total Possible Points: 2
Item 5 - Predict increase in length of rubber
band. Makes reasonable prediction, based on the data presented
in the table or graph.
Total Possible Points: 1
Item 6 - Explain reason for prediction. i)
Refers to the increase in length as read from the table or extrapolated
from graph. ii) Attempts to relate weight or number or rings to
elasticity of the rubber band. iii) Response is consistent with
data in table or graph.
Total Possible Points: 2