Knowledge building dynamics are central to scientific communities and involve dialog, debate, inquiry, and contested reasoning. Refining and developing knowledge is an oft missing dynamic in precollege educational programs. Practical reasoning and human decision making are essential epistemic and social dynamics in knowledge-building struggles and quests for the truth. Implications are presented for how a "Context of Development" approach can address "knowledge about science" learning goals and provide a framework for embedding struggles into the design of investigations and inquiries. The goal is providing learners/citizens with opportunities to acquire and make sense of evidence and then deploy that evidence for evaluating and explaining natural and social systems.