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Throw Yourself Like Seed

I spent a good part of the afternoon writing based on a book by Ralph Siu, The Tao of Science. I wrote and broadened the scope to include the Tao of Technology and the Tao of Learning or Education. I grabbed a couple of other books because words like communion and humility came up in relationship to leadership. I refer to Educating for Humanity a lot. and it is one of my most well-used books. An article had this beautiful poem about life`s abundance by Miguel de Unamuno. The way (the Tao) I look at life and my perception is one which is life-giving or not. I think this holds in terms of my interactions with other beings. Life is not separated into fragments but lived wholly and fully with reverence.

Shake off this sadness, and recover your spirit;

sluggish you will never see the wheel of fate

that brushes your heel as it turns by,

the man who wants to live is the man in whom life is abundant.

Now your are only giving food to that final pain

which is slowly winding you in the nets of death,

but to live is to work, and the only thing which lasts

is work; start again to turn to the work.

Throw yourself like seed as you walk, and into your own field,

don`t turn your face that would be turn to it to death,

and do not let the past weight upon your motion.

Leave what`s alive in the furrow, what`s dead in yourself,

for life does not move in the same as a group of clouds;

from your work you will be able to gather yourself.

Chair Building

I use this lesson plan as an activity in the Grade 7 Science Structure and Forces unit. The students work in pairs.

  • Students draw a plan for the chair design.
  • Concepts to Include might include corrugation, lamination, and triangulation; design considerations such as arches, beams, trusses, and columns; and show an understanding of what fastening techniques for this design i.e. friction fit, mass, and glue, staples, rope, tape (within reason), or nails or screws (within reason).
  •  Consider properties i.e. stability, brittleness, ductility, hardness, plasticity, compression, and tensile strength.  Students need to consider deformation, structural stress, structural fatigue, and possible structural failure. What are internal forces (mass of materials) and external forces (load on the chair).
  • What role do aesthetics play i.e. symmetry and appearance? What is the chair used for?
  • Students use recycled material i.e. cans, plastic containers, and cardboard (boxes, tubing, and pieces).
  • Students construct and track changes. The original chair design might be altered depending on material availability, functionality, and durability.  They should test the chair as they build.
  • I limit class time to 2-3 classes. Most materials are found at home and students can receive help from family, friends, or neighbours.
  • I email parents and tell them they are consultants, who can offer expertise, guidance, and time unavailable in the classroom. Parents are good about insuring students do the lion’s share.

Students are innovative. One student included pop bottle (he told me it was for pop) holders in the arms of a deck chair. Another student gathered discarded pizza boxes after hot lunch and used those.

Assessment is a rubric. A criterion is I test the chair. Its ability to hold my 250 pounds, give or take, is part of the challenge. Only one chair collapsed under my mass. It lacked support.

This is a Grade 7 project, but I think other can modify it for other grade level needs. Students can work in pairs.

Cautionary note: I allow nails, screws, and tape as fasteners, but within reason. The first time I did this activity a student built a nail chair. He used so many nails it is doubtful they were recycled.

Here are some examples of this year’s chairs.

This chair is made from used pressure treated lumber and plywood. The back folds forward and the student used baling twine he got from the farm as the hinges.

This chair is constructed from willow. The willow qualified as recyclable as the students were going to have to dispose of the willows when they cleared underbrush anyway. The only thing missing is a cushion. These students could go into business selling yard furniture.

Although this stool did not have triangles for stability, the centre piece helped in that respect. When I sat on the stool, it was wobbly, but with my mass it became less so. The students used baling twine as the only fasteners. One of them has horses and these were available.

This chair is built from recycled wood and a discarded cushion. The students gathered the wood from the neighbourhood and a neighbour helped. He drilled tap holes for the screws.

Whales Forever

This is not about whales per se. Several years ago, my Grade 8 class struggled with the simple machines unit in Science. I proposed an alternative assessment route. Instead of writing a test, they could apply their learning and build a complex machine. They were all over it, but I had to come up with something and began a search of the Internet. I found an idea called Whales Forever and modified it to fit my needs. It has been a success ever since.

1. Whales become stranded on beaches around the world and Whales Forever is concerned with the survival rate of beached whales. This environmental organization rescues whales and returns them to open water quickly so they will not perish. Whales Forever announced a contest for Grade 8 students to create a prototype machine which would safely lift a stranded whale onto a hover craft so it could be transported back to open water as it receives medical treatment.

2. Students design and build a machine which with a minimum mechanical advantage (MA) of 4. The machine consists of at least two simple machines. Mechanical advantage is calculated output force divided by the input force.

3. The machine will lift the whale a height of 10 cm and lower it 5 cm onto the simulated hovercraft. The whale is simulated by a resealable plastic bag filled with marbles or sand. Students can hand position the ‘whale’ in a harness which is part of the system to begin the lifting process.

4. Students sketch exploratory labelled diagrams of their chosen design including measurements indicating critical components i.e. simple machines used, gears, and drive trains. They provide mechanical advantage calculations.

5. Students use available materials i.e. desks, stools, tables, retort stands. Last year, a student used a Meccano set and this year students used K’Nex. They are not allowed to use a motorized system. They use planes, levers, pulleys, screws, wheel and axles, and perhaps a wedge.

6. Students give a written reflection outlining the strengths and weaknesses of their design including written suggestions for improvement.

7. Students make a 4 minute presentation to the board of directors of Whales Forever.

I use a rubric and assess the design including diagrams, the effectiveness of the prototype, the reflection, and the presentation.

Here are some examples of this year’s products.

Whale Saver constructed from K’Nex. You can see the harness on this one. It had a mechanical advantage of about 15. The one challenge with the K’Nex is hooking up the scale. It took some maneuvering.

This one was homemade. It had a mechanical advantage of 20.

These students used materials from the classroom primarily. It had a mechanical advantage of about 8 or 9.

This was another K’Nex design. The thing on the right is a rock wrapped in paper with a face on it. The rock countered the weight of the whale as it was lifted. This machine had a mechanical advantage of about 10.

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