Energy saving and carbon-emissions reduction (ESCER) are widely regarded as important issues for progress towards ensuring sustainable forms of economic development. This Taiwanese study focuses on the effects of a series of educational activities about ESCER on students' knowledge, attitudes and behavior. Sixty fifth-grade students from two elementary school classes were assigned to an experimental group, and 59 from two others to the control. Covariance and qualitative data analysis were conducted after 14 lessons on the topic in both "treatments." The following key findings emerged. First, hands-on "energy-saving house" learning activities seemed to have positive effects on students' knowledge, attitudes, and behavior toward ESCER, even as the design of authentic learning activities was recognized as not being as closely aligned to the students' daily lives as they could have been for achieving behavior-related outcomes. Second, students demonstrated slight gains in conceptual knowledge and procedural knowledge via the hands-on activities, but some ESCER misconceptions persisted. We conclude that students' learning processes, prior learning and authentic contexts for ESCER-related work should not be ignored in the attempt to link knowledge to action in teaching and learning activities.