Posts Tagged education
1994 Hot Wheels car wins 2018 Christmas time trials on Corkscrew Crash track
Santa brought my grandson Archer a Mattel Corkscrews Crash track this week. Archer’s been busy ever since running time trials in triplicate on the 48 Hot Wheels cars in his set and computing averages for each group of runs. Considering he’s only in first grade, Archer shows a lot of promise for being an engineer like me, my father and my grandfather (if I do say so myself). However, he needs a bit of work on deciphering how to record times that end in single digits on the hundredths, for example, Archer wrote a time of 1.08 seconds as 1.8—without the zero. I’m working on this. Decimals are tricky for needing to kept in place.
Being overwhelmed with data, I sampled out 12 cars from the dozens that Archer has tested thus far and typed the results into Design-Expert® software’s tools for this one-factor (categorical) comparative experiment. They came out highly significant with very clear divisions between the slowest and fastest cars. (Full disclosure—Archer did not fully randomize the trials, another thing for me to teach as he matures, but I will wait a year or two to try.)
The fastest run—taking less than 1 second to slither through the Corkscrew-was made by a vintage Malaysian entry: the 1994 Mattel Hot Wheels Power Piston Viper Strike. You can see this highlighted in the graph (the bars show least significant differences at 95% confidence).
The trials are continuing at my house now. I am reverting to my ‘Hot Wheels shuffle’ stride when walking about—carefully limiting my step height to avoid stepping on the metal cars. The ones with the pointy fins can be very painful. But it’s all for a great cause. Experimentation!
Dream come true: Homework banned and school days delayed
The Wall Street Journal this week reports that, for the sake of “student wellness”, school districts across the USA are now banning homework [1].
The U.S. Department of Education figures that, on average, high-school students (those without the “get of jail free” card) spend about 8 hours per week on extracurricular assignments. Girls spend an hour more than the norm and boys an hour less, thus there’s a two-hour gender gap on homework. (You be the judge as to what this implies on relative intelligence. I don’t dare!)
Naturally, parents with ambitions for their son or daughter do not favor this trend to relieve academic pressure. Many evidently move their child to private schools that load on several more hours of homework every week. That would be a blow—being yanked away from all your friends at Easy Street High.
It would be worth it if more homework leads to a significantly better education. WSJ suggests that this may not be so for elementary students. That seems sensible. But what about high school? The author of The Battle Over Homework, Duke professor Harris Cooper, says that studies show a positive correlation of homework with achievement [2]. He advises that high-schoolers put in at least 90 minutes a night but beyond 2.5 hours the returns diminish (and any chance of a social life).
Meantime, other school districts, perhaps some that ban homework (that would be double dope!), have moved back their start times to provide more sleep for students. For the heads up, see these Shots from the December 12th NPR Health News on Sleepless No More In Seattle.
I can only say that my quarter of 8 am organic chemistry as a freshman at university did not go well. My notes provided a record of frequent nodding off by my pen trailing off every few lines. That was before I discovered coffee and became addicted to rising early.
Science class a real blast
Making your own erupting volcano is a classic experiment to do at home or in science class. Some, such as the ammonium dichromate one in the video, should not be done without strict supervision and safety precautions.
However, the standard experimental volcano with vinegar and baking soda generally does not cause much harm; that is, until an overzealous mom in India took it to a new level with a blast that injured 59. Fortunately, as reported here, the two students who went to hospital came out intact. Perhaps a non-working volcano might be advised in future.
Are you one of the elite 10% who can work out this test of logic?
Posted by mark in pop, Uncategorized on May 2, 2018
Four cards are laid out before you, each with a letter on one side and a number on the other. You see E, 2, 5 and F. Which cards should you turn over that will prove the following rule: If there is an E on one side, the number on the other side must be a 5? See the answer by Manil Suri, Professor at University of Maryland, in this April 15 New York Times article that asks “Does Math Make You Smarter?”.
As to whether math really does make you smarter, the answer remains unclear. However, those who do well with numbers make far more money. That is not surprising, but the multiplier may be. See this U.S. News report (or not if you failed the test above) for the statistics.
Weakest students hurt worst by shift away from face-to-face teaching
The January 21 New York Times featured a thought-provoking critique* of online courses by Susan Dynarski, a professor of education at the University of Michigan. She cited growing evidence that the trend away from classroom training in high schools and colleges hurts less proficient students who need ‘hand-holding’ from skilled teachers. However, research suggests that the greatest harm comes from courses going fully online. “Blended” training, which presents the opportunity for interaction with a flesh-and-blood teacher, evidently overcomes this disadvantage.
An interesting wrinkle on blending face-to-face with online education comes from the Massachusetts Institute of Technology. They offer free online courses on economics. Students who do well can apply for a master’s program which requires only one semester of class on MIT’s Cambridge campus to graduate. This weeds out those with weak academic skills, whereas many high schools mistakenly go the opposite route—students failing face-to-face classes get sent to remedial online classes.
“For advanced learners, online classes are a terrific option, but academically challenged students need a classroom with a teacher’s support.”
-Susan Dynarski
*”Online Courses Fail Those Who Need Help”, p3, Sunday Business Section.
Weapons of mass destruction scaled down for classroom warfare
During our freshman year in my Christian Brothers military high school, my buddy Bob sat behind me in first-hour home-room in prime position to snipe spit balls at me. When I reacted to the sting by backlashing at him, the teacher—Brother Thomas—would admonish me for disrupting the class. Devious! Nevertheless, I had to hand it to Bob for his ingenuity for classroom warfare—my superior by far.
I shudder to think what Bob could have done with the technology revealed by John Austin in his trilogy on Mini Weapons of Mass Destruction , which begins with spitball warfare and culminates in siege weapons of the dark ages. For example, check out this video of a classroom firearm sent to me by a PhD student from the Institute of Technology of Buenos Aires.
Inspired by Austin’s books, this Argentinian and conspirators set up a designed experiment that varied three factors:
- The length of the arrow (short 20 cm – long 25 cm)
- The width of the “barrel” (narrow 11 mm – wide 17 mm)
- The initial position of the arrow (p0 the firing pin will slightly hit the arrow – p1 the firing pin will push the arrow along the last 5 cm)
Bob’s spitballs did little harm in comparison to this weapon. At this rate, turtle-necks will come back into fashion, only now being made from Kevlar. Anyone who makes it through school at this rate will certainly be the fittest for surviving and ready for the dog-eat-dog corporate world.
A curve in the road to grade inflation
The New York Times Sunday Review features an opinion by Wharton School Professor Adam Grant as to Why We Should Stop Grading Students on a Curve. He asserts that his peers now give over 40% of their grades at A level—a percentage that has grown steadily for the last 30 years as detailed in this March 2016 report by GradeInflation.com. I am not surprised to see my alma mater the University of Minnesota near the top on the chart of Long Term Grade Inflation by Institution, because, after all, we pride ourselves on being nice.
During my years at the “U” most classes were graded on the curve, which Prof. Grant abhors for creating too much competition between students. However, it worked for me. I especially liked this system in my statistical thermodynamics class where my final score of 15 out of 100 came out second highest out of all the students, that is, grade A. Ha ha. This last week President Obama chastised the U.S. press for giving Trump a pass based on grading on the curve. I see no problem with that. ; )
I do grant Grant an A for creativity in coming up with a lifeline for struggling students. He allows them to write down the name of a brighter classmate on one multiple choice question. If this presumably smarter student gets it right, that question earns full credit. My only suggestion is that whomever gets called in the most for providing lifelines should be graded A for being on top of the curve. But then I see nothing wrong with rewarding the best and the brightest.
College textbooks up over 1000 percent since ’77
Bernie Sanders say it’s time to make college tuition free. That would really be radical. A more attainable goal is to make textbooks more affordable. According to an NBC story posted just prior to the current school year, college textbook prices have risen 1,041 percent since 1977, now amounting to over $1200 per student per year. My high school classmate Mark Perry, Professor of Economics at University of Michigan, warns that:
“College textbook prices are increasing way more than parents’ ability to pay for them.”
This tide of expenses for books has been slowed somewhat by the advent of rentals, e.g., $34 for one semester versus $157 to buy Montgomery’s 8th Edition of Design and Analysis of Experiments.
Another way to save that no one dreamed of in ’77 is by buying an e-textbook—Montgomery’s DAOE book costing only $67 in this format.
However, the big breakthrough in reducing the cost of college comes from the University of Minnesota’s Open Textbook Network (OTN), which began offering textbooks for free three years ago. Students over this period saved an estimated 1.5 million dollars, primarily over the past year.*
Professor Gary Oehlert of U Mn School of Statistics—a long-time advisor to Stat-Ease and author of A First Course in Design and Analysis of Experiments**—provides this endorsement of this worthy initiative by my alma mater: “There are several other similar open textbook depositories (OpenStax, etc), but OTN was one of the first to have reviews for the books as well as perhaps being the only one to have a support model for obtaining serious reviews of the books. It also has a broader range of texts than one might anticipate, with math books ranging from high school level through some fairly advanced topics.”
Powerful forces from for-profit publishers and authors who prefer being paid for their hard labor will naturally restrict the spread of free books. Even so, the OTN will certainly put a damper on the rampant inflation of the cost of texts. That will be a big relief for hard-pressed students and their parents.
*Source: “One for the Books”, Minnesota Alumni magazine, Winter 2016, p.12.
**Freely available here under Creative Commons license
Technology advanced beyond any hope for healthy curiosity
I am watching the Syfy’s series “Childhood’s End” this week. It is based on a science fiction novel by British author Arthur C. Clarke, one of my favorites growing up. One of the main characters is a very bright boy who at the end of the premier episode last night becomes an astrophysicist, despite this scientific profession being made entirely superfluous by the advanced technology of the alien Overlords.
This morning Robert Scherrer, the chairman of the department of physics and astronomy at Vanderbilt University, lamented in an editorial* for Wall Street Journal that children no longer have any reason to be interested in science, mainly because most of our household gadgets fall into the category of magic—alluding to Clarke’s observation that “any sufficiently advanced technology is indistinguishable from magic.”
“The world’s now placid, featureless, and culturally dead: nothing really new has been created since the Overlords came. The reason’s obvious. There’s nothing left to struggle for, and there are too many distractions and entertainments.”
― Arthur C. Clarke, Childhood’s End
Crater Experiment Makes a Big Impact
Posted by mark in design of experiments, science on June 25, 2015
Craters are crazy and cool. One that is quite amazing was created by the Barringer Meteorite that crashed into Arizona about 50,000 years ago with an explosion equal to 2.5 megatons of TNT. Based on this detailing of what a 2 MT bomb would do I figure that Barringer would have completely wiped out my home town of Stillwater, Minnesota and its 20,000 or so residents, plus far more beyond us. The picture my son Hank took of the 1 mile wide 570 foot deep crater does not do justice to its scale. You really need to go see it for yourself
as the two of us did.
Because of my enthusiasm for craters, making these rates number on my list of fun science projects in DOE It Yourself. As noted there, members the Salt Lake Astronomical Society wanted to drop bowling balls from very high altitudes onto the salt flats of Utah, but workers in the target area from the U.S. Bureau of Land Management objected to the experiment.
Kudos to science educator Andrew Temme for leading students through a far more manageable experiment shown in this video. In reply to me asking for permission for providing a link to his fantastic impact movies Andrew gave me this heads-up. “I attended a NASA workshop to get certified to handle real moon rocks and meteorites at the NJ State Museum in Trenton. This lab in the educator guide suggested mixing up your own lunar powder and throwing objects to simulate impact craters. When I got home I ran the lab with a few of my classes and then made the video. I used a Sony handheld camera that had a slow motion setting (300 fps).” Awesome!
The other day I went up to the 9th floor of my condo building in Florida and tossed a football down on to the parking lot. I am warming up to heaving a 15 pound mushroom anchor over on the beach side from atop one of the far pricier high rises along the Gulf. However, I have to wait until the turtle nesting season is over.