201. Teaching by Feel

I taught science for 27 years in a small school in California. At first it was science and everything else, but each year I had more science classes until I retired teaching science full time. A few years before that, while I was teaching five science classes and one class of perspective drawing, our shop teacher left. I volunteered to keep his class open, so for two semesters, I taught shop. That is when I instituted Pounding Day.

Pounding Day came from my firm belief that kids learn best with their minds when they are also learning with their bodies. This is not the same thing as “hands on”, which is a good idea that too often deteriorates into doing arts and crafts instead of science.

Pounding Day is practice. If you want to learn to add, you practice your addition tables. If you want to be LeBron James, you practice basketball. Driving nails is no different. It makes no sense to drive your first nail into a project you have just spent a week measuring and cutting. Your first nail should be into something disposable, because is it will kink and flatten.

During the first week of class, I gave each student a hammer, two dozen 16 penny nails, and a chunk of 2 x 4. After minimal instruction, I turned them loose.

You’ve never heard such noise. OSHA would not have approved. My friend Adrianna did, however. Every Pounding Day she waved encouragement as she drove her herd from the exercise yard to the playing fields. Adrianna taught PE; she understood kinesthetic learning.

Kinesthetic learning also works for science.

Old science texts used to have kids making up pulleys from sewing thread spools. Modern technique uses prepackaged kits with flimsy plastic pulleys and underweight weights. You tell a kid that he has doubled his mechanical advantage, but he can’t tell because the whole setup is so lightweight he could easily pick it up and hurl it at his buddy in the next row.

Not good enough. Not at all good enough. When I was a new teacher, I built 2 x 4 frames, bought sash weigh pulleys and down-rigger cannonballs. Cannonballs are two and a half pound lead weights used for summer deep lake fishing. When one of my students doubled his mechanical advantage, he could feel the difference.

(Yes, I painted the cannonballs so my students would not be handling lead.)

I also built a leverage demonstrator, consisting of a 2 x 4 base with a moveable fulcrum, heavy spring load, and a mattock handle lever. I only built one because there was a dangerous amount of force involved, so I never let students use it unless it was braced by my adult strength.

fulcrum demo

With the fulcrum in the middle of the handle, the downward force is equal to the force of the spring. With the fulcrum near the end of the handle, I couldn’t budge the thing myself. With the fulcrum near the spring, the smallest girl in the class could move the handle with one finger.

If you have earned your students’ trust, and if you are careful not to bruise fragile egos, you can have a lot of fun pitting big boys against little girls in contests of strength rigged to let the little girls win.

[Safety notes: If the fulcrum is next to the spring and a student pushes down, then lets go, the handle will fly 180 degrees to the left and conk whoever is sitting there. Beware. If the fulcrum is far from the spring and your heaviest student jumps up and throws himself on the end of the handle – and they will – you had better be strong enough to keep the whole mechanism from tipping sideways and crunching you both. If you aren’t strong enough, don’t let them do it.]

Our final pulley experiment moved outdoors where I had suspended a bosun’s chair from a basketball goal. Students sat in the chair with the arrangement of pulleys over their heads and lifted their own weight off the ground.

When we did inclined planes, I brought a wheelbarrow, 2 x 12, and concrete blocks from home for the day. I let a student sit in the wheelbarrow while another ran him up increasingly steep ramps. Change students and repeat.

If the subject is force, middle schoolers need to feel that force in their hands and arms, not just calculate forces and imagine how they would feel.

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