Communicate a problem, design, and solution.
The teacher should have available one Lego kit per group (2 students per group is ideal). Other design tech building kits would be possible as well. The teacher should also have at least one standard-size brick, a couple of spring scales, and an area (a sand table with "glacial" ice is ideal) that is covered with ice which can be used for vehicle evaluation. To make the glacier, use a sand table or similar space. Layer rocks, and snow below the water. Freeze water on top, let melt unevenly and refreeze. Expose the top to winds, shaking, or a high-powered fan to create ridges. Create a crevasse proportional in size to the area.
Basic Lego kit, spring scales, brick, "glacial" ice covered area
Two one hour class periods if you choose the "quick" activity.
Engagement and Exploration (Student Inquiry Activity
Show students pictures of the glacier surface over which Bancroft and Arnesen will ski 2,400 miles. (Use a US map and figure 2,400 miles in various directions so the students will get an idea of how very far that distance is.) Ask how many of them have ever cross country skied. (Allow time to share what cross country skiing is like and what the equipment is like.) If your students have never been on X-C skis, have a pair available for them to look at. If you do not have access to X-C skis, have your students look in books or on the internet. Explain that these two women need to tow all their belongings behind them. Brainstorm what kind of vehicle could be designed to carry all their belongings. Decide what qualities it should have (weight, length, structure).
Divide the students into teams giving each team one complete Lego kit with which to work. Explain that the team is to design and build a light-weight vehicle that will carry a brick while registering the least amount of pound pull on a spring scale as the vehicle is pulled across the "glacial" ice.
Hand out the worksheet below to guide the teams.
When the vehicles are complete, have each team look at all the vehicles and predict which one will weigh the least and require the least amount of effort to pull.
Test the vehicles on the ice. Place the vehicle to be tested behind a designated start line. Attach the spring scale to a "rope" six to nine inches long depending upon the length of the ice surface. Stand on the far end of the ice and begin to pull the vehicle. Register the amount of work required on the scale. Keep track of the results on a large piece of chart paper.
Vehicle design from a side view.
What technology have you chosen for that part of the sled which will come in contact with the ice? (i.e. flat bottom, wheels, treads, runners)
Why have you chosen this parcticular design?
What problems did you have building the vehicle?
Predict which vehicle will weigh the least and require the least amount of effort to be pulled on the ice.
Why did you choose this vehicle?
How much did your vehicle weigh? ___________________
How many pounds did the spring scale register when you began to pull your vehicle? _________________________
Was your prediction correct? _________________________
Would you now change your vehicle?________ If yes, how? why?
Discuss why the vehicle that weighed the least and required the least effort to pull did. Look at the design. This may result in looking at two different vehicles. Could the two designs be combined? Brainstorm how improvements to the vehicles could be made. Finish completing the worksheet.
Elaboration (Polar Applications)
Log on to the Bancroft Arnesen Expedition at http://www.yourexpedition.com. a trans Antarctic trek. Compare and contrast the vehicles the class teams made to the ones being used on the trek across Antarctica. Discuss what simple machines were used to make the human work load lighter.
Have students write in their science journals about this experience as it relates to the Antarctic trek. What thinking processes and problem solving do the students feel they held in common with the Bancroft/Arnesen team? How were the solutions the same/different? How does this experience guide their thinking as far as the time it must take to organize a trek of this size to such a remote area of the world?
Exchange (Students Draw Conclusions)
Using journal entries for reference, have a class discussion about how the sleds used by Bancroft and Arnesen were similar to and different from the Lego vehicles constructed and tested by the class. Have a picture of the explorers' sleds for all to see. At the close of the discussion, students should have a good understanding of and be able to list the criteria necessary to make a good sled for a trek across glacial Antarctica.
Evaluation (Assessing Student Performance)
The teacher can use the student vehicles, the worksheet and the journal entries as well as oral parcticipation in the discussions to assess the level of engagement and understanding of the students. Rubrics could address design technology and problem solving skills to assess and be filled out by the student and teacher together.