Standardized tests can overload working memory far more than regular classroom tests, given the added importance of following test mechanics, the inability to look things up, and the likely higher levels of anxiety. When students are anxious, the first skill that is often affected is working memory. As a result, even students with fine working memory in a regular environment could have much more difficulty with working memory demands on standardized tests. Also, most standardized tests do not allow students to use reference materials and/or calculators. The option to look up facts, vocabulary, or formulas reduces the demands on working memory.