Write equal parts of one whole
Choose one whole, then read a fraction as equal parts and the number of those parts taken.
Begin with the activity ↓Does one piece tell us how much?
One of four equal parts of a whole is 1/4. The denominator counts equal divisions; the numerator counts parts taken.
Three people want to share a chocolate bar. Unlike indivisible marbles, the bar can be split. Choose the entire bar as one whole and divide it into three equal parts. Each part is one of those three.
Write this piece as 1/3, read one third. The 3 counts equal parts dividing one whole; the 1 counts parts taken. A number written in this way is a fraction.
Two of those parts make 2/3. The lower number is unchanged because the piece size did not change. Taking all three parts gives 3/3, the entire bar, or 1.
The lower number is the denominator; the upper number is the numerator. Remember what they count before memorizing the names. With three unequal pieces, a particular piece is not automatically one third. Equal division matters.
Half a small bar and half a large bar are both 1/2, but the amounts may differ. To compare actual amounts, the wholes must have the same size. State what counts as one whole alongside the picture.
Listen one paragraph at a time
If piece count and whole size became mixed
Draw two identical wholes. Divide only one: the pieces still cover exactly the same whole.
Now change it yourself
Change the number of equal parts and parts taken separately. Try all parts and no parts.
1/4 · One outlined strip = one equal-size whole
The denominator is a positive whole number, never zero. This lesson divides equal-size wholes into equal-size parts.
Try with paper and objects
Draw equal-size rectangles and divide them at equal intervals. Shade parts taken and label one whole.
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3/8 · Eight counts equal divisions and three counts parts taken.
Does your explanation include these ideas?
Speak, point or draw on paper. Explain the reason, not just the numerical answer.
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Partition the interval from 0 to 1 equally and locate a fraction as a distance from zero.