Anyone who has ever taught eighth graders knows that keeping their attention during the last few weeks of school is a struggle. Engineering activities are are great way to maintain interest and enthusiasm while continuing to build the skills students will need throughout high school.
In their excitement to get to the "fun part of the activity", students often rush through the planning phase which ends up costing them time and effort in the end. This activity is designed to demonstrate the importance of planning and sketching ideas.
I begin this lesson by asking students to explain the reasons scientists and engineers sketch out experimental set ups or design plans. Students are able to state a wide variety of reasons, including items such as communicate ideas to others, focus and solidify their own ideas, keep them on track and save time, save money and materials by having a clear vision of what you are trying to accomplish.
I go on to have students list the elements they believe are essential in a good sketch. The following images show some student work:
As you can see from the student work, they have a pretty good idea of what is required in a sketch.
I next use the SKETCHING PowerPoint to introduce their task. The following video explains how I use this PowerPoint and provides some details about the activity.
Students are divided up into groups of 2 and are given 2 pieces of paper in different colors. They also need scissors and tape. Students are told to build a box with a hole that can be used to catch a grasshopper. To keep track of whose work is whose, they must put their initials on the inside of the box. With our experience catching spiders, students really think they will be hunting for grasshoppers so they are pretty focused on making a sturdy box (at least those with some building skills). Little do they know that this is really an exercise in sketching and we will not be looking for grasshoppers any time soon. The following images shows you some sample boxes created by 2 groups in two different classes.
Once the build time is over, students are instructed to create a sketch of their box. Students should feel free to refer to the list of "things that should be part of a sketch" they created during the warm up but I do not remind them of this (by this time of year they should really know to do this on their own). The Student Sketch Examples show that, for the most part, students do understand the elements of sketching but there is not one perfect example.
Once all building and sketching is complete, I collect all of the boxes and put them out-of-sight in the closet and collect and redistribute the sketches to different groups. These new groups are told to build the box based on the sketch in their hand. Groups are not able to ask the creators any clarifying questions, they just need to interpret the drawing as best they can (this is why I prefer to swap the work between different classes).
This is both fun and frustrating for the students, but they definitely get the idea that there are critical pieces of information that must be included in sketches. Once students have completed their new box, I have them find the original to compare. Students then critique the drawing they were given and record on the sketch what worked well and what information they wished they had been given. The following images show the origninal boxes next to the boxes based on the sketches.