From biology teacher Shannon Muskopf's extensive website for biology teachers and students, Biology Corner, comes this collection of lesson plans, classroom activities, and PowerPoint presentations related to Ecology and Environmental Issues. Guided by a student-centered pedagogy, many of these lessons include in-class simulations or online virtual labs. For example, in the lesson Estimating Population Size, students learn how biologists capture and mark select animals in order to gauge their population via an online Biology Corner simulation or by simulating the measurement process using beans, beads, or pennies. Meanwhile, another classroom activity uses cards to help students evaluate how predator and prey relationships shift over time. Other topics addressed in these lessons and activities include biomes, random sampling, "designer" dogs, and human population growth. These lessons can be easily downloaded as PDFs and incorporated into life science or biology classrooms or in community-based learning settings.