Add and subtract fractions with unlike denominators (including mixed numbers) by replacing given fractions with equivalent fractions in such a way as to produce an equivalent sum or difference of fractions with like denominators. For example, 2/3 + 5/4 = 8/12 + 15/12 = 23/12. (In general, a/b + c/d = (ad + bc)/bd.)
What do you do with students who already get their fraction operations? Give them a contrived project about recipes or pizza slices? Make them solve annoyingly hard practice problems? Please. Here, we get students thinking in a whole new way, pondering which has more power, the numerator or denominator.
Students try to reach a specified number by adding and/or subtracting three fractions using only the digits 1 through 6. This set of challenging math puzzles comes from the series Advanced Common Core Math.
Here's a project for students who have mastered adding and simplifying fractions. Students are given a plot of land to break up into seven unequal pieces.