Creating graphical representations can foster knowledge gains on science topics in elementary school students by promoting active integration and translation of new information. Collaborating on joint representations may encourage children to discuss and elaborate their knowledge. To foster productive interactions, children may greatly benefit from additional guidance through collaboration scripts or careful group composition. In this study, we investigate the effects of script support and group composition by social preference on children's learning processes and outcomes in a collaborative drawing setting within science education. The script foresaw a phase of individual preparation and prompted learners to engage in critical interactions. Group composition was based on children's preferences for peers to work with. Results show that whereas the drawings of unscripted children depicted the concepts to be learned more adequately, scripted children acquired more domain knowledge during the experience. We discuss how a script can facilitate learning through collaborative drawing by imposing additional challenges on children's interactions.