Number activity worksheets are valuable cognitive training tools designed to target multiple cognitive domains, including information processing speed, numeric calculations, working memory, visual discrimination, and visuospatial skills. These worksheets require users to visually discriminate number lines while remembering instructions that dictate how to manipulate the digits on the line. This printable guide provides an in-depth exploration of number activity worksheets and their role in cognitive training, offering evidence-based strategies for enhancing cognitive skills and promoting cognitive wellness.