Brigid Barron and Linda Darling-Hammond summarize three , often overlapping families of inquiry-based learning: "project-based, "problem-based" and "learning through design". A key conclusion of their review of research evidence is that students learn more deeply when they can apply classroom-gathered knowledge to real-world problems; inquiry-based approaches are important ways to nurture communication, collaboration, creativity and deep thinking. Second, inquiry-based learning depends on the application of well-designed assessments, both to define the learning tasks and to evaluate what has been learned. Thirds, however, the success of inquiry approaches tends to be highly dependent on the knowledge and skills of those implementing them. If these approaches are poorly understood and mistaken for being unstructured, their benefits are substantially reduced compared with then they are implemented by those appreciating the need for extensive scaffolding and constant assessment to inform their direction.