Page 148 - Balancing between the present and the past

Chapter 6
6.4.6 Implementation fidelity
The implementation fidelity of the experimental and control condition was checked by post-intervention interviews (cf. Nelson, Cordray, Hulleman, Darrow, & Sommer, 2012). In the post-intervention interviews, we asked all the teachers to score how each lesson activity of the experimental and control conditions was implemented (0 = not implemented at all, 1 = partly implemented, and 2 = fully implemented). Table 22 presents the average implementation scores of the different lesson activities in both conditions on the 2-point scale.
Table 22. Implementation scores for the lesson activities (maximum score = 2.00)
Experimental condition
1. Case to enhance awareness of present-oriented perspectives 1.60 2. Task to reconstruct the historical context 1.60 3. Explanation of the case 1.48 4. Historical empathy task 1.12 Control condition
1. Prior knowledge activation 1.90 2. Teacher lecturing 1.98 3. Individual assignments 1.66 4. Whole-class discussion 1.36
6.5 Results
6.5.1 Historical contextualization
Table 23 presents the students’ mean historical contextualization pre- and post-test scores for the two conditions (experimental and control). The two conditions differ only slightly in their mean pre-test scores, but the mean post-test scores differ to a much greater extent. To assess the comparability of the conditions prior to the intervention, we evaluated the differences between the students’ pre-test scores in the different conditions. This evaluation revealed no significant differences (F(1,129) = 0.18, p = .89, = .00). We did find a significant difference between the students’ post- test scores in the different conditions (F(1,129) = 10.70, p = .001, = .08).
To examine the gains made by the experimental group, a paired sample test was conducted that revealed a significant difference between the students’ pre-test and post-test scores in the experimental condition; t(100) = -2.37, p = .02. To further assess the gains of the experimental group, an effect size was calculated. Morris (2008) describes an effect size for the pre-test-post-test-control design where the standardized effect of the treatment is defined as the difference between groups
Lesson activity
Implementation score
146