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"It seems only fitting to explore the role of questions in education by asking questions about the process of doing so. I propose that we start with the customary way of framing this topic and then proceed to questions that are deeper and potentially more subversive of traditional schooling. 1. WHICH QUESTIONS? To begin, let's consider what we might ask our students. The least interesting questions are those with straightforward factual answers. That's why a number of writers have encouraged the use of questions described variously as "true" (Wolf, 1987), "essential" (Simon, 2002), "generative" (Perkins, 1992; Perrone, 1998), "guiding" (Traver, 1998), or "fertile" (Harpaz & Lefstein, 2000). What the best of these share is that they're open-ended. Sometimes, in fact, no definitive right answer can be found at all. And even when there is one - or at least when there is reason to prefer some responses to others - the answer isn't obvious and can't be summarized in a sentence. Why is it so hard to find a cure for cancer? Do numbers ever end? Why do people lie? Why did we invade Vietnam? Grappling with meaty questions like these (which were among those generated by a class in Plainview, NY) is a real project . . . literally. A question-based approach to teaching tends to shade into learning that is problem- (Delisle, 1997) and project-based (Kilpatrick, 1918; Blumenfeld et al., 1991; Wolk, 1998). Intellectual proficiency is strengthened as students figure out how to do justice to a rich question. As they investigate and come to understand important ideas more fully, new questions arise along with better ways of asking them, and the learning spirals upwards. Guiding students through this process is not a technique that can be stapled onto our existing pedagogy, nor is it something that teachers can be trained to master during an in-service day. What's required is a continual focus on creating a classroom that is about thinking rather

"The transition from unicellular to multicellular life was one of a few major events in the history of life that created new opportunities for more complex biological systems to evolve. Predation is hypothesized as one selective pressure that may have driven the evolution of multicellularity. Here we show that de novo origins of simple multicellularity can evolve in response to predation. We subjected outcrossed populations of the unicellular green alga Chlamydomonas reinhardtii to selection by the filter-feeding predator Paramecium tetraurelia. Two of five experimental populations evolved multicellular structures not observed in unselected control populations within ~750 asexual generations. Considerable variation exists in the evolved multicellular life cycles, with both cell number and propagule size varying among isolates. Survival assays show that evolved multicellular traits provide effective protection against predation. These results support the hypothesis that selection imposed by predators may have played a role in some origins of multicellularity."

"Imagine you could use any kind of small head difference in a river or canal. The power those drops contain might surprise you. We created a technology that can make use of all these small waterfalls or rapids in a way that's safe for the environment. Gone are the days that communities had to choose between having power or fish to eat. Our robust and fish friendly vortex turbiness will generate energy 24/7 at an incredibly low cost of energy. That way you can have a project with high return on investment that improves the world just that little bit. Now, if you look at a river or canal, you'll notice that it's full of these small cascades, that's how nature builds rivers. We have created a distributed turbine system that can combines a large amount of turbines into one big virtual hydropower powerplant. These virtual hydropower plants can be as large as 10MW in power output. That's the power production of a small city! We can do this because our civil structures are designed to be easy to install, and the electronics and robust power take-offs are designed to keep working with minimal maintenance. The energy produced can be directly connected to your appliances or machinery, and at the same time connected to the national distribution grid, so you can inject the unused power to it, maximizing the revenue through a net billing connection."

"Una cúpula geodésica es una estructura formada por triángulos que componen una superficie inscrita en una semiesfera. Las cúpulas geodésicas se construyen a partir de los cinco poliedros regulares, que como sabemos son el tetraedro, el cubo, el octaedro, el dodecaedro y el icosaedro. A partir de ellos, para generar una cúpula geodésica de orden n lo que hacemos es dividir las aristas de cada cara en n partes iguales, unir los n-1 puntos obtenidos en cada arista para subdividir la cara en varias caras proyectar los vértices de cada una de esas caras hacia la esfera definida por los vértices iniciales del poliedro regular tomando siempre como punto de partida del rayo proyectante, el centro de esa esfera. El número de triángulos en los que se divide una cara depende del número de subdivisiones que tiene su lado (orden de la esfera geodésica). Para orden n el número de triángulos correspondientes a una cara se puede calcular del siguiente modo: ..."