Group

M

SD

n

4^th grade

CK_Pre

−0.531

0.632

110

CK_Post

0.467

0.907

110

CK_Follow

−0.053

0.822

110

6^th grade

CK_Pre

−0.297

0.476

148

CK_Post

0.472

0.886

148

CK_Follow

0.044

0.761

148