West Point Bridge Extensions

An excellent way to extend the West Point Bridge Design software is to add your own sets of criteria and constraints. I give the students real-life type situations that they have to follow. This is an example assignment from this year:

You will be designing bridges to meet certain criteria and for different situations. For each bridge you are to design, you will need to keep track of the following in written form:

1. The problem (Hint: You are designing a bridge)
2. Any criteria and constraints for that particular bridge.
3. Your brainstormed ideas
4. Your evaluation of those ideas
5. The design chosen and why
6. The WPBD file
7. The test results
8. Any redesigns you have made (in general. You don't have to write down every single time you changed a member size)
9. If you were successful or not and if not, why?

Bridge #1: This bridge is for our local contest (Code RELC). There are no additional constraints. You are trying to make the cheapest bridge possible. Grades will be given based on placement in our local contest.

Bridge #2: Due to aesthetic reasons, the Copper Canyon Bridge must be built as an arch bridge. The span of the bridge must be no larger than 20 feet. The citizens of Copper Canyon have appropriated $300,000 for the construction of their bridge.

Bridge #3: Due to a mistake at the steel factory, all of the steel sent for the bridge is in 4 meter lengths. You may cut the steel to make shorter members, but no member may be longer than 4 meters. Cost is not a concern, as the steel company will be paying for their mistake. You may change the thickness of the members, as long as you change all of them to the same thickness.

Bridge #4: Due to a material shortage, the Johnson Creek bridge cannot contain more than 125 meters of steel. The town government has also set the minimum deck height at 8 feet to accomodate flat barges that use the creek, as well as a $230,000 maximum cost.

For each bridge, you must have all parts of the design process written (#1-9.)

For the first bridge, I use the Local Contest option. There are no additional constraints other than those imposed by the software itself. The other bridges have added constraints that make them a little more challenging. As with most design projects, there is no "right" answer, but you will find that the more criteria and constraints you add, the more "convergent design" you will have. The students designs will start to look similar.

Just another way to get more use out of an already great (and free) software program

TTFN

Teachtron is on Hiatus, But I Have a Good Reason Why!

So it's been a little while, but we've had a lot going on around here. First was christmas vacation. Then was ISTF projects when we got back. Then was ACT Workkeys testing (which is great for high schoolers in Florida.) And we just finished National Engineers Week, in which we competed in the US Army Corps of Engineers Career Day, JETS TEAMS, and The Robotics and Automation Society Robotics Competition, which is a collegiate competition but we won first and second anyway. We would have done Mathcounts, too, but it was the same day as JETS.

Why am I telling you this? For the most part, all of these competitions were free. Didn't cost us a dime. The only one that did was JETS, but I know some schools that got a company to sponsor the $200. We used old equipment and legos for the robots.

National Engineers Week is a great time to show off your program and make others in education and the professional community aware of you. You need to take the standpoint that it is their responsiblility to help you in engineering education, because they are going to reap the benefits of a well educated, competitive workforce.

It's up to you to teach it.

TTFN

The argument against turn-key, out of the box engineering curricula

I should preface this post by saying that all of the pre-made engineering curricula out there are excellent; they were all put together with educators and engineers, subject matter and teaching experts from around the country. If you can afford to implement any of them, I suggest you do it. I have the Amatrol system, which I inherited when I came here. However, I'm going to make the case that these are unnecessary if you have the right mindset, dedicated teachers, and a few good ideas.

The first point I would like to make is against the necessity of the off-the-shelf curricula. Before any of these curricula existed, engineering still was taught. The Brooklyn Bridge, Empire State Building, and Transcontinental Railroad were still designed, built, and are performing admirably. I do agree, however, with the strides that the curricula have made to get engineering education in to the middle and elementary grades, but I disagree with the fact that they are motivating more students to study engineering. As the population has grown in the last fifty or so years, the number of students pursuing engineering majors per capita has actually decreased in the last 20 years. I think that the introduction of these plug-in curricula was a reaction to this trend, not a proactive step for the future.

The next point is concerning the cost. As with many other areas of education, prices for textbooks and other curriculum materials are quite high, and many schools find that they have teachers and students that would benefit from a technology program only to find out that they cannot afford to implement it in their schools. This is especially true with engineering and technology curricula, which is comprised of multiple trainers and electronic components, all needing their own computers. This argument lends itself to a haves vs. have nots issue. Schools in lower-income areas (both rural and urban) do not have access to the necessary funding. Any student should have access to an solid pre-engineering foundation.

One other problem that I have seen with engineering curricula, although I understand that it has a place, is what I call the "whiz-bang" effect. The whiz-bang effect happens when you take a group of students and teach them only the fun things: rockets, bridges, catapults, etc. without engaging them in the behind-the-scenes math and physics that makes them work, or the effects of those different technologies on societies. It's easy to fall into this trap, as I've done myself. It's easy to teach students when they are doing something they enjoy. But sometimes, as a teacher, you need to make sure the students understand the reasons they are doing what they are doing. The turn-key curricula are getting better in this regard, but it takes a strong teacher to actually put it to practice in the classroom. I've seen more than a few teachers just "skip" the math parts because "It's just so hard to get the students to do it." This also present problems down the road. Students sometimes think that engineering is all fun and projects. When they get to college and have to explore engineering design to its full depth, they hate it and want to quit. They didn't know what was coming.

Teachers can make up for a lack of specialized equipment by using their imaginations. Almost any object can be used to teach engineering principles. All objects have material properties, and can be combined to build structures, apparatuses, testing equipment, and other things. I'm talking about any objects: paper, pencils, paper clips, rubber bands, and other things you have laying around your classroom. This also helps with the cost issue. Like I said before, I have a bridge-testing machine, but I prefer to just put the bridge between two tables and hang weights from it.

As I wrote at the beginning of this post, I don't want to turn anyone off of using a pre-built curriculum if you can afford it; I just want it to be known that you shouldn't feel discouraged if you can't. It just takes a little more work.

Of course, we're used to a little extra work. That's why we're teachers.

TTFN

Website Review: www.jets.org

(review as of 12/17/2008)

Description (from site):

"JETS is a national non-profit educational organization dedicated to promoting engineering and technology careers to our nation's young people. Since 1950, JETS academic competitions, educational activities, and career guidance resources have been exciting students about careers in engineering and technology."

JETS, or Junior Engineering Technical Society, is a great website with quite a few resources for students, teachers, and parents. I, in fact, make liberal use of JETS practice problems in my classes. They have monthly and weekly problem sets, mostly (if not all) for the high school level. The problem sets do an excellent job of applying math and critical thinking skills to real-world type problems. The problems come in .pdf format with the answers attached, so you'll have to figure out a way to remove them if you are using them for a test or quiz. The practice problems also prepare students for the TEAMS competition sponsored by JETS. TEAMS is national academic competition challenging students to apply math and science to solve real-world engineering scenarios.

Also for teachers, JETS sponsors the National Engineering Design Challenge, an engineering design competition that allows students to explore, research, design, and build a working prototype to empower individuals with disabilities to succeed in the work force. These make great science-fair type projects.

For parents and students, there is a great newsletter that comes out monthly which spotlights different kinds of engineers. Well worth the read, and you can sign up to have it automatically emailed to you each month. There is also JETS Explore, which allows students to take a look at different engineering fields, as well as some real-life jobs and the engineers that have them. There is also a tool, called JETS Assess, which allows students to answer a series of questions, create a job profile, and generate a list of the engineering careers that best suit them. The bad news is that a complete profile report will cost you $12.95. You can also buy a set of assessment materials for a class.

All in all, http://www.jets.org/ is a great website for students, parents, and teachers alike that are interested in learning about and teaching about engineering. Highly Recommended!

TTFN

I'm proud of my students, are you proud of yours?

This is about a third of my seniors. On Monday we went to BAE Systems here in Jacksonville, which is a manufacturer of law enforcement and forensic supplies. I always worry a little about taking my students out in public, but they continue to surprise me. The hosts at BAE were raving about how intelligent and well-spoken our students were. They also agreed to be a business partner.

I wonder, as I look out at my senior class, how many of them would be going to college if they did not enter into our program. I'm sure a lot of them still would, but because of us and what we do, they all will. I've seen the change in them, especially this year. We had an interview workshop that required them to dress up. Most of them grumbled at first, but I found out that they enjoyed the attention the other students gave them. They voted to have "Dress for Success" Thursdays every week.

I guess that's why we do it.

TTFN

Engineering on the cheap...doing it with Paper!

Of all of the common materials that can be used to teach hands-on engineering concepts, probably the most flexible (no pun intended) and easily available is ordinary computer paper. One of our most successful projects is the Paper Bridge, a task that involves having the students construct a bridge out of the previously mentioned paper. This is the way I do it:

I give the students a short lesson on bridges, after which I give them a little time to come up with a bridge design. The students typically will pick a truss-type bridge, usually because the other two types (Suspension and Arch) do not lend themselves well to paper construction. The key here, depending on the level of student, is to introduce the idea of criteria and constraints. If I was teaching this to 3rd graders, I may not limit their materials, I may only tell them the length of the span they have to cross. When I teach this to 10th and 11th graders, I will typically impose very tight constraints and criteria. In class right now, for instance, my 10th graders are working on a 60cm bridge, using only 10 sheets of paper and masking tape. I've done it with seniors where I've given them 5 sheets of paper, 25cm of tape, and had them build bridges that were 60cm in span as well as 10cm x 10cm in height and width. That takes some thinking.

I also have the students do a presentation about their bridges, as well as a similar bridge somewhere in the world. Again, based on the level of your students you could stop there, or go as far as analyzing the economic impacts to a city if a particular bridge was not there. This could be an in-class discussion, or homework, etc.

The possibilities are almost limitless. We have paper towers, paper testing to investigate material properties, and we can even do papier-mache to look at composite materials (a papier-mache column with spaghetti reinforcements is especially impressive if you do it right.) The US Army Corps of Engineers also has a really good e-book about using manila file folders to construct bridge beams at http://bridgecontest.usma.edu/...

...Which segues me into my next point. The previous project is the no-tech version. You can make it low-tech if you have a couple of computers by using the West Point Bridge Designer software. It's free, so you don't have to worry about coming up with any funding. It is a good tool for kids check the stability of their bridges before they build them, and also where the tension and compression is (you could go into beam buckling and tension equations if you want to, but it is probably best left to high school teachers.) It also runs on just about any computer, from Win98 on up.

The high-tech option is left to those teachers which buy or already have a bridge-testing apparatus (I actually have one, but I prefer to just put the bridge between two tables and hang cupfulls of penies from it.) You can measure the force vs. deflection, and graph it and look at the flexibility of different types of bridges.

Hope you can put this to good use. I'll have some worksheets up in the near future.

TTFN

Facilities and Demographics Disclaimer

OK, maybe the title is a bit much, but I just wanted to let anyone reading this blog (which, so far has a readership of zero as far as I can tell) a little about the school I teach at, and why the things I'm spouting off about will work in just about any school.

First, about facilities. I've been to visit other schools with brand new lab facilities, or remodeled 2,000 square foot auto shops. While those types of facilities made me jealous, I had to think as to the reason I was there. I was the one telling those teachers how things should be done. They had the great facilities, but I was the one that was making engineering work in my school.

My school was built in 1926. I have a classroom and a half, and only because someone in the past knocked down the wall between my room and the office next door. I have four tables and 28 chairs, and some lab benches with about 15 computers on them. No Internet. But it works, and if it works here, it'll work almost anywhere.

A quick note about demographics: Jacksonville is a large, urban school district, the 13th largest in the country (or thereabouts.) Our students are 63% black, and the rest a mix of white, Asian, and Hispanic. 43% of our students get free lunch. And Florida, in the land of paradise, is 50th in public school spending out of our 50 states. And we make it work.

So again, I'm just trying to quash any excuses about why this or that won't work. We need to get engineering concepts integrated into our schools from the bottom up. Whatever it takes.

(shoot, I'll probably use this as the intro to the book!)

TTFN