Biomodeling is the study of the structures and behaviors of interacting biological entities such as molecules, cells, or organisms. While physical and chemical processes give rise to various spatial and temporal structures, even the simplest biological phenomenon is infinitely more complex (Kling 2004). Over the past decade, much of biomodeling research has focused on developing mathematical and computer models that replicate the characteristics of a cell or other biological organism (Anderson, Chaplain, and Rejniak 2007; Chauvière and Preziosi 2010). At colleges and universities, mathematicians, biologists, physicists, biochemists, and computer scientists are developing ways to study biological problems using mathematical methods, probability theory, and stochastic (randomly determined but statistically analyzable) processes coupled with computer modeling. This article describes hands-on activities that introduce teachers and students to biomodeling. The activities align with the "Next Generation Science Standards" (NGSS Lead States 2013; see box, p. 51).