Explain to the students that they likely have experienced fractions already in their daily lives. To illustrate this concept, use examples such as taking a slice of pizza away from the whole.
Use visual drawing to help explain the principles to visual learners. Try drawing a rectangle and shading half of it, then asking how much of the rectangle has not been shaded. You should get a response of half, which you can then explain as a fraction.
Explain the numerator and the denominator. Tell your listeners that the numerator is the top number and the denominator is the bottom number. Continue by explaining that the denominator is the full number, and the numerator is the amount of the full number that is left.
Try using coins to further explain the concept of fractions. Explain that a quarter is 1/4 of a dollar and that four quarters, or 4/4, equals one full dollar.