`Lesson for Multiplying and Dividing Fractions with Post It NotesRobert Foote                   Disney Magnet School                               4140 N. Marine Drive                                Chicago IL 60613                                (773)534-5844Objectives:Students will use postit notes to measure various dimensions of rectangles to nearest fraction of an inch.  This lesson is intended for seventh grade.  Students will divide fractions to predict the number of postits needed to meet the length and width of the rectangles. Materials Needed:3 by 3 inch postit notes1 1/2 by 2 inch postit notesdifferent sized rectangular shaped paperrulers and yardsticksStrategy:Show students a piece of 8 1/2 by 11 inch piece of paper.  Ask students how many postit notes it would take to meet the length and width of the piece of paper of each size.  Explain the algorithm for dividing fractions to see mathematically how many 3 by 3 postits will fit and how many 1 1/2 by 2 will fit.  To illustrate this, divide 8 1/2 by 3.  You get 2 5/6.  Take the 3 by 3 postit notes and place them along the 8 1/2 side of the paper.  Carefully cut the overlapping part of the last postit note.  Measure the part remaining on the paper and it should be close to 5/6 of 3 or 2 1/2.  Measure the part you cut and it should be 1/2.  Do the same procedure with the other dimension of the 8 1/2 by 11 paper by dividing 11 by 3.  Place the postit notes along the 11 inch side and verify the math.  Then do the same with 1 1/2 by 2 inch post it notes. After finishing this demonstration, pass out two different size rectangular sheets of paper and have students measure the sides.  Working in groups, have students determine mathematically how many of each kind of postit notes it would take to cover both dimensions of both sheets.  The students, after doing the math, will then tell you how many postit notes they need.  Give them exactly what they ask for and have them cut out the fractional part of the post it note they need by measuring it first.  Display the student's work on the board and discuss strategies for finding the answer and ways the answer could go wrong.  Precise measurement is very important for accurate results.  Performance Assessment:This activity in itself is a wonderful performance assessment.  You may modify the sizes of the rectangles or simply use straight lines.`