Have
students work in pairs or small groups [depending upon the best working
arrangement for your students]. The students may have noticed that the
same fraction (1/2, for example) is not always equivalent (or the
regions are not always congruent). For example, have the students
compare the answer to the following questions:
The green triangle is what fraction of the blue rhombus ? [1/2]  The red trapezoid is what fraction of the yellow hexagon ? [1/2]  How can and both be equivalent to ______? (Query the students until they are able to articulate that the meaning or value of _____ relative to the whole.) 

These and other questions are presented on the Region Relationships 4 activity sheet. Working in pairs, allow students to complete these questions.
On the activity sheet, students will explore other fraction
relationships in which the fraction is the same but actually refers to
two different wholes. For example,
Have the students make similar comparisons using two yellow
hexagons as the whole. Continue investigating relationships with other
wholes (e.g., three or more yellow hexagons). You may choose to have
them record the relationships in a math journal to which they may refer
later. Each group should record relationships on chart paper to share
with the whole class. As each group shares, have students add to their
journal any relationships that they did not discover on their own.