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"Generating electricity is not only inefficient, it also makes pedal power less sustainable, less robust and more costly. To begin with, batteries have to be manufactured, and they have to be replaced regularly. This requires energy, which can completely negate the ecological advantage of pedal power. According to this research paper (pdf), the embodied energy of a 150Wh lead-acid battery (like the one offered with the Windstream pedal power generator) is at least 37,500 Wh, which equals 250 full charges of the battery (more sources: 1/2). In other words: if you can deliver 75 watts of power to the battery, you have to pedal for 500 hours in order to generate the energy that was needed to manufacture the battery. Because the life expectancy of a lead-acid battery can be as low as 300 discharge/charge cycles (sources: 1/2), you are basically pedalling to produce the energy required to manufacture the battery. If you also factor in the embodied energy of other electronics and parts, the ecological advantage of a pedal powered generator connected to a battery becomes rather doubtful. It might costs more energy than it delivers."

"1. The teacher is choosing the technology. It's not always possible, but when you can, let the students choose, and see what happens. Not all of them will be able to. Some need help; so let other students help them. 2. The teacher is choosing the function. This doesn't mean you can't choose the function, but if you students can't control the technology the use nor its function, this can be problematic: the learning is passive from the beginning. 3. The teacher is determining the process. To an extent you have to, but don't overdo it. 4. The technology is distracting. If the technology is more magical than the project, product, collaboration, process, or content itself, try to muffle the bells and whistles. Or use them to your advantage. 5. The technology isn't necessary. You wouldn't use a ruler to teach expository writing, nor would you use a Wendell Berry essay to teach about the Water Cycle. No need for a Khan Academy account and a fully-personalized and potentially self-directed proficiency chart of mathematical concepts just to show a 3 minute video on the number line. 6. The process is too complex. Keep it simple. Fewer moving parts = greater precision. And less to go wrong. 7. Students have access to too much. What materials, models, peer groups, or related content do students actually need? See #6. 8. The teacher is the judge, jury, and executioner. Get out of the way. You're (probably) less interesting than the content, experts, and communities (if you're doing it right). 9. They artificially limiting the scale. Technology connects everything to everything. Use this to the advantage of the students! 10. They're not limiting the scale. However, giving students the keys to the universe with no framework, plan, boundaries or even vague goals is equally problematic. 11. Students access is limited to too little. The opposite of too board a scale is too little-akin to taking students to the ocean to fish but squaring of

"Because energy fuels both human development and environmental damage, policies that encourage energy demand reduction can run counter to policies for alleviating poverty, and the other way around. Achieving both objectives can only happen if energy use is spread more equally across societies. However, while it's widely acknowledged that part of the global population is living in 'energy poverty', there's little attention given to the opposite condition, namely 'energy excess' or 'energy decadence'. Researchers have calculated minimum levels of energy use needed to live a decent life, but what about maximum levels? "

Digital marketing channels are the doors to step in to create your online presence. However, every digital marketing channel cannot be equally fruitful for your business.

"This is a simple tool that uses some basic trigonometry to measure the height of trees. This tool is a 45-45-90 triangle and thus an isosceles triangle. Isosceles triangles have two legs of equal length. By using a 45-45-90 triangle to placed yourself at a distance from a tree trunk, you create an triangle where the distance from the trunk is also the height of the tree. "

"El sociólogo francés habla de la injusticia y de cómo la ideología del mérito puede esconder una apuesta por la "selección" social. François-Dubet La desigualdad y la pobreza son flagelos que aún las sociedades más desarrolladas no han podido eliminar del todo. La esperanza de los gobiernos liberales ha sido puesta en la educación. ¿Cuál es el tipo de escuela que lucha contra la inequidad social? François Dubet, profesor de sociología en la Universidad de Burdeos II y director de estudios en la Escuela de Altos Estudios de París, autor de Repensar la justicia social (Siglo XXI Editores), habló con El Espectador sobre los retos de la escuela para construir justicia social. Un concepto muy utilizado en los medios es el de justicia social, pero ¿cuál es su definición? En todas las sociedades existen desigualdades y la justicia social consiste en saber qué desigualdades son justas y qué desigualdades son consideradas injustas. Cuando decimos que esto es justo y aquello es injusto tenemos una concepción de la justicia social. Por ejemplo, podemos decir que tal salario es justo porque corresponde al esfuerzo y a la cualificación del trabajador, o que es injusto porque el trabajador no es suficientemente bien remunerado. ¿Cuál es la relación entre la justicia social y la escuela? Una escuela justa debe permitir a todos sus estudiantes conseguir logros en función de su trabajo y su talento. Una escuela es injusta cuando los logros de los estudiantes dependen de las condiciones sociales y de los ingresos de sus familias. Desde este punto de vista, casi todas las escuelas en el mundo son injustas, porque los estudiantes de clases favorecidas tienen mejores resultados que aquellos de clases desfavorecidas. En todos los países hay excepciones y algunos estudiantes de familias pobres tienen logros sobresalientes en la escuela, pero no son muchos. ¿Qué piensa de que los gobiernos prefieran becar a algunos pocos que tienen las más altas ca