Objective: Students will divide fractions and mixed numbers.
- Ask the children to remind you once more about the fraction skills we have been working on. Remind them that there is a test in a week and one day. The skills are simplifying, equivalent fractions, comparing fractions, adding and subtracting with like and unlike denominators, adding and subtracting mixed numbers with unlike denominators, converting back and forth between improper fractions and mixed numbers and multiplying fractions.
- Explain that there is one more skill that they have to learn. Considering that they learned how to multiply fractions yesterday, what skill will we be working on today? Dividing fractions.
- What is a reciprocal? Two numbers are reciprocal if their product is 1. Remind the children that product means multiplication. If that is the case, then what is the reciprocal of 5? Of 1/3? Of 2? Of ¾?
- As the children look at the numbers and their reciprocals, ask them if they have discovered a pattern. They should be able to tell you that a reciprocal is when you flip the numerator and denominator. Show them that this is true of whole numbers as well, if you write the whole number as a fraction.
- One easy way to show this is to write numbers on index cards and attach them to magnetic clips. These can be your numerator and denominator and you can flip them around.
- If you can find the reciprocal of any fraction, then dividing fractions is as simple as multiplying them. All you have to do is find the reciprocal of the second fraction and multiply. (You never actually divide when dividing fractions.)
- Finally, remind the children that if you have a mixed number, you must first turn it into an improper fraction. Also, you must simplify and turn improper fractions back into mixed numbers at the end of the problem.
- Again, Before the children complete the worksheet, they must first complete a quick review sheet. (If you prefer, they can do this afterwards.) Explain that on Thursday and Friday, certain children will be teaching the class themselves. That decision will be made based on who does the best job with the review sheets.
- Volunteers can answer certain questions on the board. The remainder of the sheet is for homework.
- Ask the children why this statement is true “Even whole numbers are actually fractions.”