A 60 minute lesson in which students will add and subtract fractions with the same denominator.
Draw a large circle on the board and divide it into eighths. Ask a student to come up to the board and colour in two pieces. Underneath the circle, write two eighths as a fraction.
Draw an addition sign next to the first circle, then draw a second circle of the same size. Divide this second circle into eighths. Ask a second student to come up to the board and colour in five pieces. Underneath the circle, write five eighths as a fraction.
Draw an equals sign next to the second circle, then draw a third circle of the same size. Divide this third circle into eighths. Ask a third student to come up to the board and show the answer of the addition sum on the third circle. Underneath the circle, write seven eighths as a fraction. Ask the students:
What do you notice about the numerator of the answer?
What do you notice about the denominator of the answer?
Why does the numerator change, but the denominator does not?
Correct the worksheet as a class. Ask the students to draw a smiley face (I can do this!), a straight face (I’m getting there!) or an unhappy face (I need some help!) on the top of the worksheet to indicate their understanding of the lesson’s objective.
Allow students who are finding the concept of adding and subtracting fractions challenging to use concrete materials to help them with the questions. For example, cut and laminate the fraction wheel pieces from the Fraction, Decimal and Percentage Wheelsso that students can physically manipulate the pieces to answer each question.
Suggested Assessment Strategies
used strategic whole class or individual questioning
observed student participation during learning activities