The biology strand of the IQWST project consists of three units, each emphasizing important ideas in the life sciences. In the 6th grade, students will learn about species interactions in ecosystems, the relationship between structure and function, and individual organisms' needs for survival.In the 7th grade, students will learn about cell biology and development of organisms, from fertilization to adulthood, as well as organ system functions. In the 8th grade, students will learn about how heritability of traits and changing environmental conditions can affect individual and population survival.

The approach of the biology strand to the life sciences is to emphasize the interconnectedness of ideas both within and across units. For example, students will learn about single-celled organisms in the 6th grade unit in the context of ecosystems and revisit the idea of cells in the 7th grade unit as they learn about the developing organism. Students will learn about how structure and function aid in survival of an organism in its ecosystem in the 6th grade but revisit structure and function in the 7th grade as they learn about why organs have particular functions. Students will learn about fertilization and development in the 7th grade but revisit the implications of genetic traits for survival in the 8th grade unit. In all three units, students will explore ideas of energy needs for survival and how survival occurs on multiple levels - individual, population, and species.

In addition to emphasizing scientific ideas, the biology units give students experience with important scientific practices. These include working with models, constructing scientific explanations, engaging in argumentation and debate, analyzing authentic data gathered either from students' own investigations or captured within complex datasets, and presenting ideas to peers in an interactive environment. Our approach is to have students learn scientific ideas by engaging in these practices - in other words, to have an authentic activity within which to apply complex scientific ideas will lead to deeper understanding of those ideas.

Technology will also be an important part of each of the units. For example, students will work with computer simulations to investigate species interactions and population levels in the 6th grade unit. In the 8th grade unit, students will use a computer tool to explore a complex database in order to investigate the cause of a sudden decline in a finch population in the Galapagos Islands. Therefore, students will be involved in both hands-on investigations in which they manipulate variables and test their hypotheses as well as computer investigations into phenomena that may be difficult if not impossible to explore in the classroom.