Both the old National Science Education Standards (NSES) and the recent "Next Generation Science Standards" (NGSS) devote significant resources to learning about human environmental impact. Whereas the NSES advocate learning about human environmental impact in a section apart from the science- content learning strands, the NGSS embed them in the core life- science and ecology learning strands. We describe a study that compared the effects of these different approaches on ninth-grade biology student learning. It found that students learned significantly more human-environmental-impact and ecological-function content when human-impact content was embedded in ecology content than when human impact was taught as a discrete unit from ecology.