Learning to categorize and sort objects and ideas is a key component to helping primary age students find and use materials in their library. When teaching students in grades 2-3 the Dewey Decimal System, consider this lesson which asks them to categorize recognizable objects into groups based on shared traits. Using concrete objects will help you bridge learning so that the more abstract concept of grouping books by similar topics is attainable for these learners. This lesson uses content from INFOhio's Educator Tools and ISearch.