Chapter 15 page 391
of this hint.
On the other hand, the teacher’s comment prompts John to a new insight of his
own: “Then any society can have a poet.” The teacher’s comment may have pushed
John’s thinking forward. Looked at from this perspective, the teacher’s comment proved
to be productive.Group Size and Composition
A final issue teachers need to consider when setting up effective groups is determining group size and
composition. Teachers often assume that an ideal group has four or five students and that it should be
heterogeneous in gender, ability, and ethnic group (O'Donnell, 2006); however, consensus on group size is
that there is no single best group size. Group size should be determined based on the task.
Groups ranging from two to six students can be effective, though for the different group sizes,
different types of instruction work best. For example, guided cooperation works very well with groups of
two, while for groups with four to six students, complex instruction, group investigation, and STAD are
effective.
The issue of heterogeneity of groups is more difficult to resolve. Heterogeneous groups have
diversity among the group members (different proficiency levels, different ethnic backgrounds, different
genders, and so on). Homogeneous groups are composed of students who are similar to each other (e.g.,
four European-American boys of middle proficiency). Table 15.4 summarizes an influential line of research
by Noreen Webb (1982; Webb, 1985), who focused on the frequency of explanation in middle school
groups working on math problems. Her work examined the effects of homogeneous and heterogeneous
groups on the frequency of explanations in groups. She focused on explanations because of her finding
(which we discussed earlier in this chapter) that explanations promoted learning in these groups.
Table 15.4
Group Composition and Learning
Group composition Frequency of
explaining
among students
Why?homogeneous groups composed
of high-ability students
low Students feel as if they already know the material and so do
not explain to each other
homogenous groups composed
of medium-ability students
high Students feel comfortable giving explanations to each other.homogeneous groups composed
of low-ability students
low Students do not have enough knowledge to provide
explanations.heterogeneous groups
composed of students of mixed
abilities
high More able students provide explanations to less able students.
However, in groups with high-, medium-, and low-ability
students, the medium-ability students tend to get left out.