Overall Performance on Content-Specific Tasks

Lego Building Steps: The children’s accuracy in completing a 6 step Lego building activity, in which they were given a series of 6 pictures depicting building steps and a novel set of Legos, was assessed by tallying the number of correct steps completed by the child. At the pretest assessment, the participants completed were successful at the task, on average, completed 4.22 of the 6 steps correctly. Building accuracy increased slightly by the posttest assessment (M = 4.78) and the 1-month follow up (M=5.04) (see the top row of Table 16 for the mean number of successfully completed building steps). The successful completion of building steps was

correlated across measurement points (rs = .28 - .51). No differences as a function of gender or grade were seen on building performance.

Strategic Talk about Building: The language used by the children to describe their building techniques was also coded to capture how many of the 6 total steps were characterized by descriptions of strategy use. As can be seen in the bottom row of Table 16, the number of

61

steps characterized by strategic talk (eg., counting, matching size and/or shape to determine the correct pieces, guessing and checking, and planning out what steps to do next) remained low and relatively stable across each assessment (rs= .33 - .37). Although some children engaged in this type of description of their building process, on average children made use of this type of talk during approximately 2 of the 6 intervals. As was the case with children’s building performance, the number of intervals in which strategy occurred was not related to their gender or grade.

Relations Between Strategic Language and Building Skill: The number of building steps during which children referenced strategy use in their descriptions of how they were building was not correlated with their building success at the pretest, but was found to be significantly related at the posttest assessment (r = .31, p < .05). This association was also not seen between the number of building steps correctly completed and language describing building at the 1-month assessment. Moreover, associations across time between these measures were identified. Table 16

Lego Building Task Performance

Pretest Posttest 1-Month

Mean (SD) Range Mean (SD) Range Mean (SD) Range

Accurately Completed Building Steps 4.22 (1.79) 0 – 6 4.78 (1.31) 0 – 6 5.04 (1.13) 2 – 6 Steps Characterized by Strategic Talk 1.87 (1.23) 0 – 6 2.00 (1.28) 0 – 6 1.85 (1.41) 0 – 6 Knowledge Assessment.

Children’s knowledge of the content presented during the instructional unit was assessed with a series of questions. These questions reflected two aspects of the content shared with the children throughout the lessons and included both factual information (e.g., names of the parts of

62

a gear train and information related to simple machines) as well as knowledge of building and problem solving strategies related to Lego activities.

Factual Knowledge: As anticipated, on the pretest assessment of content knowledge, the children provided very few correct responses (M = 1.83). Performance on this measure increased considerably by the posttest (M = 11.42) and the 1-month follow up (M = 10.07). Although a great deal of variability was seen in performance on this measure, no differences were found in the percent of correctly answered questions based on gender or grade. Additional descriptive results can be found in the top line of Table 19 below.

Table 19

Knowledge Assessment Scores

Pretest Posttest 1-Month

Mean (SD) Range Mean (SD) Range Mean (SD) Range Factual

Knowledge 1.83 (1.83) 0 - 5 11.42 (5.58) 3 - 24 10.07 (4.82) 3 - 23 Strategy

Knowledge 1.64 (1.53) 0 - 5 7.78 (3.38) 1 – 15 6.91 (2.74) 0 - 12

In addition, as can be seen below in the top left corner of Table 20 below, significant correlations were identified across all three assessments of factual knowledge. Although strong linkages were seen between children’s performance on the pretest and posttest (r = .44, p < .01), the strongest relations were identified between children’s posttest scores and those they received one month later (r = .88, p < .01), suggesting that there was consistency in the amount that children remembered across time.

Strategy Knowledge: The children’s strategic understanding, as assessed on the basis of their open-ended responses to a series of building scenarios, was also limited at the initial assessment. As can be seen in bottom half of Table 19 above, children reported 1.64 strategies about building techniques and ways to solve Lego building challenges before participating in the

63

experiment. This result indicates that, on average, the children had a general understanding of at least one or two Lego-related building techniques in advance of the instructional unit. By the posttest, children were nominating 7.78 unique strategies on average, and continued to offer similar amounts of information on average one month later (M = 6.91).

On this measure (see the bottom right corner of Table 20), the children’s responses in advance of the experiment were not significantly correlated with those given at the posttest (r = .24, p = .09). A linkage between children’s strategic knowledge at the posttest and 1-month assessments, however, was identified (r = .64, p < .01).

Relations between Factual and Strategic Knowledge: Concurrent linkages between factual and strategic knowledge were observed at the pretest (r = .59, p < .01), posttest (r = .47, p < .01), and 1-month assessments (r = .45, p < .01). As can be seen in the bottom left corner of Table 20, time-lagged correlations were also observed across the three assessment points. Table 20

Linkages between Knowledge Measures across Pretest, Posttest, and 1-Month

Facts Strategies

Pretest Posttest 1-Month Pretest Posttest Facts Posttest .44** 1-Month .48** .88** Strategies Pretest .59** .39** .42** Posttest .29* .47** .52** .24 1-Month .09 .46** .45** .37** .64** Note. *p<.05, **p<.01

3.2.3 Measures of Memory Capacity and Receptive Vocabulary