When course was taught

# of students

Average pre-test score (points)^

Average post-test score (points)^

Mean difference (points)

Standard deviation

Paired t-test p-value*

Winter 2013

20

9.4

12.2

2.8

2.58

0.000

January 2014

27

7.4

10.9

3.1

0.97

0.000

Spring 2014

12

8.3

10.6

2.3

1.92

0.019