Watch the video above to see a very recent advance in molecular science — the kind that would take months or years to reach classrooms before the edge of human knowledge moved online.
The researchers placed a thin film of water containing single stranded DNA molecules between a glass surface and a metal-coated base. By heating a spot on the base with an infrared laser a thermal gradient is created in the fluid layer, with cooler fluid at the top. This pushes the DNA molecules towards the top of the film. The laser is then scanned in a radial pattern from the centre; as the laser spot moves it heats up the fluid locally causing changes in viscosity which result in contraction and expansion of the fluid either side of the moving spot, which causes the fluid to flow outwards, away from the centre. The layer of fluid above this moving ‘belt’ moves in the opposite direction to conserve mass. In this way, the molecules, which have been drawn to the upper layer of the fluid by the initial heating, are pulled towards the central spot, where they accumulate.
Weinert and Braun showed that high concentrations of DNA can be accumulated within a few seconds when carried on the conveyor. ‘The mechanism does not require microfluidics, electrodes, or surface modifications,’ the researchers say. ‘As a result, the trap can be dynamically relocated. The optical conveyor can be used to enhance diffusion-limited surface reactions, redirect cellular signalling, observe individual biomolecules over a prolonged time, or approach single-molecule chemistry in bulk water.’
How much could today’s teen learn by working in Thomas Edison’s lab? A new report from the Lemelson-MIT Invention Index says: “A vast majority of teens (79 percent) believe there is value in hands-on, project-based science, technology, engineering and math (STEM) education and learning in high school.”
Even fairly late in the 20th century hands-on lab experience meant working in a place that still looked much like Edison’s laboratories. Even fairly late in the 20th century, teens learned much of their science hands-on in brick and mortar labs at school or on apprenticeships.
Edison’s laboratory had no computers, no Internet access to information and no real-time collaboration. His references came from books and letters. You will think of other differences. Have we switched our viewpoint away from idealizing a school lab as something like Edison’s was?
Today’s teens have computers in their pockets, do not remember the pre-Internet days, and collaborate throughout the day in real time. Only at school are they primarily required to use books to find information. You will think of other ways today’s teens are different from those of us who felt we were in touch with the real world when we had created a chemical reaction in a test tube on a school lab table.
On the Edison National Historic Site page where the above picture is found, the legend under the picture reads: “Thomas Edison always maintained that chemistry was his favorite science, and chemistry was indeed integral to most of the laboratory’s work.” Educators need to figure out what a lab would look like today for a gifted young inventor with the potential of a Thomas Edison. A teen Edison today would surely stand proudly among devices to access the virtual world for information and virtual experimentation.
We must be sure our 20th century minds are released from idealizing old Tom Edison’s lab before we can think freshly about what today’s teens need to nurture their inventive gifts.
This morning the New York Times has a story on the front page that is ten years old in its timing. It asks—as if it were newsworthy—whether virtual science is a good way to teach high school students. It seems the vaunted College Board has decided to challenge the online labs that provide experiments in mixing chemicals, dissecting tissue, and other expensive and now rare on-hands school laboratory traditions.
Maybe in 1996 these would have been worthwhile questions. But in the meantime here are some changes virtual science has caused: Detailed, realistic online labs have replaced NO labs that students would find in many schools. Virtual experiments offer experiences considered too dangerous to be done in a brick and mortar lab. Lessons using tissue spare the lives of experimental animals. Virtual experiments offer a broad range and variety of levels of difficulty impossible in a classroom full of kids.
Nonetheless complains, “Trevor Packer, the [College] board’s executive director for Advanced Placement [:] “You could have students going straight into second-year college science courses without ever having used a Bunsen burner.”
In 2006, using a Bunsen burner is an insurmountable obstacle for teenagers in failing schools, developing countries, and places with strict fire codes. With today’s technology you could easily do a virtual Bunsen burner lesson on your mobile phone screen. Yet the vaunted Gray Lady New York Times, who probably carried a story about Robert Bunsen’s burner invention in 1855, is giving front page coverage to going back to 19th century schooling. Here is some flavor of that from the NY Times article:
John Watson, an education consultant who wrote a report last year documenting virtual education’s growth, said online schools had faced lawsuits over financing and resistance by local school boards but nothing as daunting as the College Board. “This challenge threatens the advance of online education at the national level in a way that I don’t think there are precedents for,” Mr. Watson said.
The board signaled a tough position this year: “Members of the College Board insist that college-level laboratory science courses not be labeled ‘A.P.’ without a physical lab,” the board said in a letter sent to online schools in April. “Online science courses can only be labeled ‘A.P.’ if the online provider” can ensure “that students have a guided, hands-on (not virtual) laboratory experience.”
But after an outcry by online schools, the board issued an apology in June, acknowledging that “there may be new developments” in online learning that could merit its endorsement. . . .
[And what does the accrediting industry itself—of which the College Board is a prime example— show when it measures online labs?] On the 2005 administration of the A.P. biology exam, for instance, 61 percent of students nationwide earned a qualifying score of three or above on the A.P.’s five-point system. Yet 71 percent of students who took A.P. biology online through the Florida Virtual School, and 80 percent of students who took it from the Virtual High School, earned a three or higher on that test.
“The proof is in the pudding,” said Pam Birtolo, chief learning officer at the Florida Virtual School.
Weinert and Braun showed that high concentrations of DNA can be accumulated within a few seconds when carried on the conveyor. ‘The mechanism does not require microfluidics, electrodes, or surface modifications,’ the researchers say. ‘As a result, the trap can be dynamically relocated. The optical conveyor can be used to enhance diffusion-limited surface reactions, redirect cellular signalling, observe individual biomolecules over a prolonged time, or approach single-molecule chemistry in bulk water.’
This morning 
