Investigating the Earth System provides a modern approach to teaching undergraduate, introductory-level Earth Science and Physical Geology laboratories with the aim of creating science-savvy citizens capable and willing to make informed decisions about key environmental issues, including where to live. To achieve this end, the manual integrates three novel design elements while still covering traditional topics such as rock and mineral identification, surface and subsurface water resources, and map reading and interpretation. The first is to thoroughly and repeatedly engage students in all steps of the scientific method, including data collection, hypothesis construction, and hypothesis testing. By doing this in a highly conspicuous and intentional manner, the effect is to instill the experiential learning necessary for individuals to think like Earth scientists as a matter of routine. Second, the activities promote the relevance of the material at nearly every turn by providing thought-provoking queries based on real-world examples. Finally, and most crucially, the manual culminates in two capstone activities built on the guided inquiry approach. These activities allow students to apply their hard-won knowledge and skills to gather, synthesize, and analyze data obtained from publically-accessible online databases, thereby engaging in informed decision-making centered on real-world problems that pertain directly to Geology and Earth Science. Notably, these capstone activities have been fashioned so that they can be easily and quickly custom-tailored to meet local circumstances and interests. To help ensure student success, Investigating the Earth System is completely self-contained. All information necessary to complete each lab, including fundamental underlying principles and concepts, is provided on a just-in-time basis in the introduction to each lab activity. In addition, each lab is accompanied by a PreLab activity designed to allow students to hit the ground running when they enter the lab room. Because of this approach, most activities require little to no introduction in the lab room, thereby making the most of limited lab time and, in some cases, allowing for two activities to be completed within the time constraints of a traditional lab session. Investigating the Earth System, now in its second edition, is time-tested and incorporates feedback from thousands of undergraduate students at Eastern Michigan University gathered over 25 years of continuous use. A clear alternative to the traditional plug-and-chug method, the 16 activities that comprise this manual are nonetheless easy and foolproof to apply in practice, and are appropriate for majors and non-majors alike. "