In this article, we present two studies that helped us understand the kinds of support that students need to learn science successfully from design activities. Both were enacted in the context of an approach to learning science from design called learning by design (LBD). In our first study, we designed and integrated a paper-and-pencil scaffolding tool, the design diary, into an LBD unit to support students' design-related activities. We learned two important lessons from the first study. First, we refined our understanding of the processes involved in designing and the ways we might present those processes to students. Second, and more important, we observed that in the dynamic, complex environment of the classroom, not all of the scaffolding could be provided with any one tool or agent. We found that students need multiple forms of support and multiple learning opportunities to learn science successfully from design activities. In our next study, we provided additional support through an organized system of tools and agents. Our analysis of data from the second study leads us to believe that supporting multiple students in a classroom requires us to rethink the notion of scaffolding as it applied to groups of learners in a classroom. We put forth the notion of "distributed scaffolding" as an approach to supporting hands-on inquiry learning in a classroom.