ConcepTest: Oldest Rocks
Question:
Carefully examine the relative positions of the lettered arrows on the timeline below and estimate the ages represented by each arrow. Identify which letter corresponds most closely to the age of the oldest known rock on Earth.
a. C
b. D
c. E
d. F
e. G
a. C
b. D
c. E
d. F
e. G
Student Responses:
The correct response is C.
Percentage of students choosing this answer. (% Before Discussion/% After Discussion):
a. C(3%/0%)
b. D (13%/0%)
c. E (40%/73%)
d. F(24%/20%)
e. G (20%/7%)
in a small (< 60 students) environmental geology class
If you would like to help acquire more Before and After statistics for this example, please contact the authors (see link at top of page).
