Dear all,

I kindly need your help. Here is my background.

I am a secondary school teacher.

I taught two different classes in the same form last year. Two different teaching method were used on these classes. In order to compare their academic performance under the various teaching methods, what should I do? Here are some questions which I am thinking about.

1.

If the scores of final exam of two classes are used as the only

dependent variable, the two teaching methods are treated as the independent variables. (a) As all scores of two classes are well collected, could I treat I got the population mean, population variance….

(b) As I got the population information, could I simply compare their mean scores to justify their performance?

2. I wonder, could I need other statistics such as t-test or ANOVA to do the comparison?

(a) If the answer is “yes”, what are the

**rationale**?

(b) It seems t-test is not suitable, as we got the population information instead of sample information. Does it make sense?

(c) How about ANOVA? Is it better than t-test?

3. In most of secondary assessments, their distributions are skewed (negative or positive. For skewed distributions, comparing means, t-test, ANOVA are still valid? IF no, what should I do?

Thanks in advance. Best Regards,

LCY