We examined whether children would show different change-patterns in their strategy use when administered a number of series completion tasks that were presented within a dynamic testing format utilizing a graduated prompts approach. The role of working memory was also examined. An electronic console using tangible objects with sensors enabled the detailed recording of children's responses and solution times. We hypothesized that children who received training (i.e. who were involved in dynamic testing) would progress to more advanced strategy use than non-trained children, and that this would be evident for both verbal and behavioral measures of strategy use. We also sought to examine whether more advanced strategies would be employed by children with higher levels of WM-capacity. It was found that dynamically tested children shifted their verbal strategic behavior to a more advanced level. When examining the behavioral measure, it was found that some children showed the same progression but others who had performed at an advanced level in the pre-test shifted their strategy, unexpectedly, to a heuristic form. Working memory capacity did not appear to play an important role in differentiating between trained groups. Dynamic testing, using electronic console and tangibles with sensors, enabled us to identify strengths and weaknesses in children's learning. (Contains 6 figures and 2 tables.)