This collection of 5 worksheets provides immediate feedback for students as they are self-checking. They are fun and satisfying for students because the answers correspond to letters that decode secret messages. On the first worksheet students write equations of lines in slope intercept form when given two points, a point and the slope, and the slope and the y-intercept. The second worksheet asks students to look at six graphs of lines and to use those graphs to identify the lines' slopes and y-intercepts. To complete the third self-checking decoder-style worksheet, students will identify the slope of a line and a particular point through which it passes when given the equation of the line in point-slope form. On the next algebra worksheet students will write the equation of lines in point-slope form when given the slopes of the lines and a point that each one passes through. On the fifth worksheet students will change the form of given equations of lines in other forms such as in slope-intercept form and in general linear form to point-slope form. Students enjoy solving the puzzles and discovering the secret messages while they get instant feedback upon each problem. You may also be interested in other PUZZLE MATH worksheet and books including, "PUZZLE MATH: Mixed Derivatives", and "PUZZLE MATH: Trigonometry and Logarithms".