Design Your Shopping Bag Lessons
In designing your shopping bag lesson plan, your probably
won't get very far without doing the activity
yourself. Just as students need to become familiar
with the materials and the product they are designing,
you'll need hands-on experience with shopping bags before
designing your lessons.
With a personal investigation under your belt, you'll
probably find an overall outline for the activity handy
-- you can get this by reviewing the three-phase Video
Timeline for this task. You should be ready to apply
a modified Grant Wiggins-style Backward
Design approach to creating your own shopping bag
lesson. Briefly, this involves asking: "What understanding
do I want my students to achieve?" and "What evidence
will demonstrate such an understanding?" (Wiggins says
you should really start with answers to these questions,
then pick tasks that will support students
in achieving these goals. By having the shopping bag
task already in mind, you would then be doing something
akin to reversed backward design!)
Here is a short list of possible skills and concepts
that you might consider aiming for with your students:
- Develop a shared vocabulary for describing different
bag designs and their performance when loaded.
- Conduct experiments so that students test a single
design variable per iteration.
- Communicate to other classmates the results of
testing and design suggestions (see Design
- Describe bag redesign decisions via explanations
based on experimental results.
- Predict and diagnose bag failures accurately, and
explain choices using appropriate terminology.
- Work collaboratively in groups, with an awareness
of different roles played and needed by a team.
Select some or all of these goals, or other goals related
to Standards, and ask, "How could my students demonstrate
these understandings to me and others?" You can
then structure your lessons so that they support students'
growth towards these objectives. Do you want your students
to do qualitative testing of bags to failure (by hand
or foot), or quantitative testing? Should they choose
bag materials or will you just give them paper lunch
bags to convert into shopping bags? Do you want kids
to have more or less tape for reinforcement? Will you
show students any DITC videos -- as with Bag
Types & How They Fail?
You may want to review DITC's Ways
of Naive Designers page in preparing this lesson.
In planning this activity, you might also want to review
Hard About a Topic as you identify key concepts
and devise powerful questions that you want students
to address. In addition, you may want to think about
which one design strategy you might choose to emphasize
with this task by reviewing pages in What
Is Design? For instance, the Research
design strategy is well represented in students' scavenger
hunt and ensuing discussion.
Here are some questions you might use to check students' understanding
of key concepts related to shopping bag and their redesign.
1. Do a triad sort of the three shopping
bags shown to the right. This involves putting two bags
in one group, and leaving the third bag by itself. How
are the two bags similar? How is the third bag different?
Was your triad sort based on characteristics that were
more surface or deep features? (See the research on
2. What is the advantage of putting a flat, thin piece
of cardboard in the bottom of a shopping bag? What kind
of failure does it help if present?
3. MOVIE 1 at the top of this page shows a hybrid
shopping bag design that mimics the function of a backpack.
Start the movie and pause it when cued so that you can
predict where you think this bag -- which may be new
to you -- will fail. After, finish watching the rest
of the movie to see if your prediction was correct.