Thursday, January 26, 2012
math facts and more...
Richard Bazeley, shop teacher in Australia, asked for permission to use this project with his kids. All my readers are welcome to use what I publish here to enhance your own child's hands-on participation in woodworking and education. So, here are the instructions. You can click on the drawing above to access it in a larger size.
I often use common 2x4 lumber for many of the projects at Clear Spring School. It can be ripped to various sizes and thicknesses, and the math facts boxes are made with hemlock or fir pre-cut studs, as these can be purchased at a low price and fair quality. The nominal size of an American 2 x 4 is 1 1/2 in. thick x 3 1/2 in. wide. I suggest adapting the size to your own system of measure based on the materials you have available.
I first cut the 2x4 in half to make it manageable on the table saw and then rip 1/4 in. strips from it. Each math facts box will require 16 inches of this stock. Rip additional material from 2x4 stock to a 1 in square dimension. To cut down on the amount of sawing in the wood shop when the kids arrive and because cutting very small blocks is almost too difficult for them, I cut the end parts using the sled on the table saw to a length of 2 in. To start the project each child is given these two end pieces and one piece 1/4 in. thick x 1 1/2 in. wide x 16 in. long from which to cut the bottom and front and back parts.
Before the kids begin, it will help to have a finished model assembled and an extra set of parts cut so I can demonstrate how it goes together.
We have a variety of hand saws available at Clear Spring School. Lately, I've been experimenting with a hand-powered miter saw to see if the kids can use it to achieve square edges and more accurate dimensions on their cuts. But I am ready to give that saw up and settle for less accurate work. To help the kids with that saw requires me rather than the vise to hold the stock for each cut, and it takes away from their opportunity to make mistakes. So perhaps best is to use a ruler, square and pencil to measure and mark the parts for free-hand cutting with the wood secured in a vise. This project is a great opportunity to teach math concepts like square, the use of the ruler or tape measure, and accurate marking on wood. Having a sharp pencil is important as it has effect on the accuracy and thickness of the marked line.
After the parts are cut, the students use our large steel stamp letter set to stamp their names in the wood on the front side of what will become their math facts box. We use 3/4 in. long #18 nails to attach the sides and bottom to the two ends pieces. It is important to carefully align the edges of the front, back and bottom with the edges of the end pieces. Expect lots of bent nails. Expect some split wood. The nails must be driven away from the center of the end pieces so that when the holes are drilled for the pencil and scissors, they will not interfere and mess up the drill bit. You will note in the illustration that the holes are off center to avoid nails.
When the math facts box is assembled, the students take turns drilling the holes. I hold the math facts box in position on the drill press as the children drill these deep holes. Because of the depth I remind them when the bit should be lifted to remove sawdust that has filled the hole causing heat to build up. We use a 5/16 in. drill for the hole for pencils and 1/2 in. for scissors and each are drilled to a depth of 2 in.
Students in first, 2nd and 3rd grade love to personalize their math facts boxes using markers. As they grow, this part of the process becomes less important to them, as greater quality of workmanship becomes too important to hide behind color.
The students make their own cards and write the correct answer on the back. We put a divider card in place so that those facts that have been mastered can be put behind the divider at the back. The math facts boxes can also be used for other things like vocabulary words and facts related to other studies.
There is one little secret to nails that most of the finest carpenters will not know but that can keep you or your students from splitting wood. To make use of this secret requires close observation of each nail as it is positioned to drive into the wood. This secret is an unintended consequence of the way in which they are made, but can be used to your advantage. When nails are made, wire is pressed between two dies that form its head and point. The process leaves a small mark across the top of the head, and two sharp edges at the point on opposite sides and parallel to the mark on the head. These sharp edges when properly aligned cut into the grain, allow the nail to pierce the wood without splitting if the sharp edges are positioned at a 90 degree angle to the direction of the grain. If the nail is positioned so that these edges parallel the grain, the point of the nail works as a wedge splitting the wood. On very small nails like those used in this project, the line at the top, and the tiny edges require close scrutiny. The edges are also sharp enough that you can determine proper orientation by feel. But learning the value of close observation is one more thing that students can learn in wood shop. This can be presented as a lesson on the value of close observation. And students can test themselves to see if the lesson is true.
With the students' names stamped on the box, and it providing a place for other important tools of learning, the math facts box serves important organizational functions that make the children much more interested in making it than for math alone. They are excited to have a place for their tools, and loved this project.
On another subject, related of course is this from the New York Times: In China, Human Costs Are Built Into an iPad
There is indeed a moral dilemma as we contemplate turning the education of our children over to high tech devices. What depth of learning do we hope for them? What kinds of moral citizens do we hope to create through our process of education?
Seriously, make, fix and create...