This chapter is in two parts and has two interwoven purposes. The first part focuses on everyday thinking, dividing discussion into sections—“Everyday Knowledge” and “Everyday Reasoning.” The purpose here is to talk more about science and science learning, to elaborate and support a view of science as "a refinement of everyday thinking," as Einstein put it. The second part delves into what happens in science class and how everyday thinking can progress toward scientific expertise. The purpose here is to discuss the rich beginnings of science in students' "everyday thinking."