PALS - Task with Student Directions

Creeping

Task with Student Directions

Grade 5-8 Performance Task
Contributed by: New York State Education Department (NYSED)
NYS Alternative Assessment in Science Project (1996)

Task:

At this station, you will observe, measure, and graph a model of slow downslope movement.

Description:

Mass wasting is the name for all of the earth processes by which gravity pulls materials down. Some of the processes, like landslides and avalanches, are rapid, while other, like soil creeping, occur so slowly that observations are difficult to obtain.

Materials:

covered 250 ml beaker containing glop
clear plastic sheet with metric scale
clipboard or stiff cardboard
stop watch
tape
blocks

Directions:

Set up the equipment exactly as it appears in the diagram above.
Uncover and quickly lay the beaker on its side so that the rim of the beaker is exactly on the 0 cm mark on the metric ruler. Use the tape to hold the beaker in the correct location.
** The glop must flow down the metric scale on the ruler. **
Start the stop watch when the glop flows across the 0 cm line on the ruler.
While the glop is moving down the board, take readings every half minute for a maximum of 10 minutes.
Read, to the nearest tenth of a centimeter, the location of the front of the glop on the metric scale. Record your observations on the data table.
After completing the readings, set the beaker upright on the table, peel the glop from the plastic sheet, return it to the beaker, and cover the beaker.

Student Answer Sheet

1. Use the data table to record your observations to the nearest tenth of a centimeter per half minute.

2. Draw a line graph of the data using time and distance as your variables. Label both axes.

Time (in minutes)	Distance (in centimeters)
0.0	0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
9.0
9.5
10.0

3. a. Calculate the rate of movement of the glop during the first three minutes of observation to the nearest tenth of a cm/min. Show your work.
Rate = distance / time

Answer _____________

b. Calculate the rate of movement of the glop during the last three minutes to the nearest tenth of a cm/min. Show your work.
Rate = distance / time

Answer _____________

4. a. Compare the rates of movement for the first three minutes and the last three minutes of observation. Using complete sentences explain why they are or are not the same.

b. How does your graph show the similarities or differences in rates that you calculated in question 3? In complete sentences, explain how your graph displays the rates.

5. a. Material that is more liquid will move downhill faster than material which is "stiffer", (less fluid or more viscous). Where would the line for a more liquid material be located on the graph?

b. This activity presented a model for downslope movements like mudflows, soil creep, or glacier activity. In nature, what could happen to increase the rate of movement of sediment or ice in these earth features.