| Factor | Kolmogorov-Smirnova | Shapiro-Wilk | ||||
| Statistic | df | Sig | Statistic | df | Sig | |
| Teachers’ professional practice | 0.148 | 385 | 0.0 | 0.897 | 385 | 0.0 |
| Academic resource endowment | 0.172 | 385 | 0.0 | 0.947 | 385 | 0.0 |
| Instructional supervision | 0.133 | 385 | 0.0 | 0.936 | 385 | 0.0 |
| School time usage | 0.196 | 385 | 0.0 | 0.932 | 385 | 0.0 |
| Teachers’ motivation | 0.184 | 385 | 0.0 | 0.866 | 385 | 0.0 |
| Parental support of academics | 0.179 | 385 | 0.0 | 0.897 | 385 | 0.0 |