Engage 4th and 5th grade early finishers with these fun elapsed time puzzle worksheets! These print-and-go crack-the-code-type duration of time or intervals activities are the ultimate no-prep resource for end of year math review, centers, stations, morning work, or sub plans. 5 self-checking mystery word puzzles to turn standard time intervals practice into an engaging, independent challenge or cooperative learning extension or enrichment challenge. . Targeted Skills Covered:Calculating elapsed