In this activity, learners solidify their conceptualization of cells by building a model of a cell in a ziplock bag. The three-dimensional nature of cells comes to life as learners use everyday objects to represent the many parts of a cell. In addition, learners can use this activity to develop a sense of scale, calculating how big a human would be if the ziplock bag cell model were really the size of a cheek cell. The quantities in the materials section are for a group for 30 learners. When choosing objects to represent organelles, it is best to avoid food items like beans and candy since they will decompose and grow mold inside slime, creating a disgusting mess.