These seven self-checking riddles focusing on adding and subtracting fractions and mixed numbers with unlike denominators are a great resource for classwork, centers, or homework. My kids love doing riddles like these (though I think what they love even more is telling me how corny the jokes are). I, of course, love being able to quickly grade an entire stack of papers!

NOTE: This product is available as part of my Adding & Subtracting Unlike Denominators bundle. This bundle includes three different sets of task cards & printables, this set of self-checking puzzles, and two sets of I Have…Who Has? cards that are only available in the bundle – and you can save over 20% on the cost of the individual products!

___________________________________________________________________________________

Common Core State Standards for Mathematics addressed:
Numbers and Operations - Fractions (NF)
• 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.) (5.NF.1)
___________________________________________________________________________________

Included:
• 7 self-checking puzzles
• answer key for each puzzle

These seven puzzles progress in difficulty level, providing a level of scaffolding as your students build their proficiency with adding and subtracting unlike denominators and allowing for opportunities to differentiate within the class. The difficulty progresses as follows:

Puzzle 1
• find sum or difference of two proper or improper fractions
• only one fraction has to be renamed

Puzzle 2
• find missing addend, minuend, or subtrahend (terms not used)
• uses only proper and improper fractions
• only one fraction has to be renamed

Puzzle 3
• find sum or difference of two mixed numbers
• only one fraction has to be renamed
• no regrouping is required for any of the subtraction problems

Puzzle 4
• subtract a mixed number minus a proper fraction
• only one fraction has to be renamed
• regrouping is required for all of the subtraction problems

Puzzle 5
• add and subtract two mixed numbers
• only one fraction has to be renamedPuzzle 6
• add and subtract proper and improper fractions
• both fractions have to be renamed

Puzzle 7
• add and subtract two mixed numbers
• both fractions have to be renamed
• no regrouping required for any of the subtraction problems

A list included in the product describes how the difficulty level progresses across the riddles. In addition, the footer on each puzzle identifies the specific skill on which the activity focuses (e.g., adding & subtracting mixed numbers without regrouping). I hope the list will help you in deciding which puzzles are appropriate for your students at a given time of year or for differentiating to meet the varied needs in your class.

There are two versions of the puzzles – one version that does not require any simplifying, with all sums and differences presented in non-simplest form, and another version that requires simplifying. I designed them this way because my own students are often at different levels of understanding when working with fractions, with some students able to quickly and fluently simplify while others are still progressing in this area. I am not always a huge stickler about students simplifying their final answers, particularly when students are still working to build their proficiency with simply adding and subtracting with unlike denominators. However, I know that some teachers feel very strongly about their students simplifying all answers, and so I wanted to provide the option of puzzles that require students to simplify to find the correct answer.

You may opt to use only the puzzles that require simplifying or only the ones that do not require simplifying. Alternately, you can use both versions, having some students complete one and other students complete the other version. Since the two puzzles are virtually identical, your students will have no idea that you are differentiating! The Table of Contents identifies the pages on which you can find the different puzzles.

There are many ways in which you can use these puzzles pages beyond the suggestions above. Your students can complete them on their own, in pairs, or in small groups. The riddles can be used as center work, drill, classwork, assessment, or homework. The riddle pages have a range of 9 to 15 problems, so none of them should take very long to complete, and keys are included for all six, so scoring should not take too long either! [Though since these are self-checking, your grading workload should be light ☺]



Looking for more practice with adding and subtracting with unlike denominators? Check out:

Foxy Fractions - adding/subtracting unlike denominators task cards + printables

Ferret-y Fractions - add/subtract unlike denominators task cards + printables

Fishy Fractions - adding/subtracting unlike denominators task cards + printables



I hope your students enjoy these resources and are able to build their proficiency with adding and subtracting with unlike denominators. – Dennis McDonald