A fraction describes equal parts of a whole. To name a fraction, count the total number of equal parts (denominator) and how many parts are being considered (numerator). A shape divided into 4 equal parts, with 2 shaded, shows 2/4.
Fold paper into equal parts (halves, thirds, fourths). Shade or color parts and describe what fraction is shaded. Use concrete objects that can be divided (pizza slices, chocolate bars) to build understanding.
You already know how to cut a shape into equal parts — for example, folding a piece of paper so both halves are the same size. A fraction is simply the name we give to one or more of those equal parts when we want to describe how much of the whole we have.
A fraction is written as one number over another, like 3/4. The bottom number — the denominator — tells you how many equal parts the whole was divided into. The top number — the numerator — tells you how many of those parts you are talking about. So 3/4 means: the whole was split into 4 equal parts, and we have 3 of them.
The equal-parts rule is what makes fractions work. If you cut a pizza into 4 slices but the slices are different sizes, calling one slice "one-fourth" would be misleading — because a fourth should always mean the same amount. Fractions are only fair and useful when the parts are truly equal. That is why your earlier work on partitioning shapes into equal parts is the direct foundation here.
Fractions appear on any whole that can be divided: a rectangle cut into thirds, a set of 6 stickers with 2 of them circled (2/6), a number line between 0 and 1 with marks at equal intervals. The shape of the whole changes, but the meaning of the fraction stays the same — denominator names the size of the part, numerator counts how many.