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El objetivo del presente estudio pretende analizar la selección de materiales curriculares didácticos y el papel que desempeñan en los procesos de enseñanza-aprendizaje. Antes de ello, se mencionará el concepto de análisis de necesidades a efectos de encontrar los mejores materiales que las puedan satisfacer. Se prestará especial atención a las posibilidades de selección, análisis y evaluación de materiales, en tanto que constituyen los principales medios de transmisión de los contenidos a los estudiantes intentando ayudarlos a desarrollar las competencias básicas establecidas en el Anexo I de la LOE. Se enfocará el presente estudio sobre materiales curriculares aplicados a la enseñanza de idiomas, hablando de las ventajas y desventajas de usarlos como recursos didácticos. Para finalizar, se expondrán algunas reflexiones en torno a la práctica docente, los libros de texto y materiales multimedia.

In this research, the adsorption of gallium onto natural zeolite (clinoptilolite) and two mesoporous activated carbons was compared and evaluated. The clinoptilolite was treated with HCl (HCPL) while mesoporous activated carbons (MCSG60A and MCO1) were synthesized by replica method, using sucrose as carbon precursor and silica gel as template. These carbonacenous materials showed large pore sizes and mesoporous surface, as well as a suitable surface chemistry for cation adsorption, which promotes a high negative charge density. On the other hand, zeolites have narrower pore sizes, which hinders the material diffusion inside the particle; however, its strength is their ion exchange capacity. Regarding the gallium kinetic studies, it is described by Pseudo-second order model for both sorts of adsorbents. MCO1 is the best carbonaceous adsorbent studied, with a capacity of 4.58 mg/g. As for zeolites, between the two zeolites studied, HCPL showed the best results, with a gallium adsorption capacity of 3.1 mg/g. The gallium adsorption mechanism onto MCO1 material is based on physisorption while HCPL is mainly retained due to an ion-exchange process. Regarding Giles classification, MCO1 isotherm described an H-4 pattern of high affinity, characteristic of multilayer adsorption. Double-Langmuir model fits properly these experimental results. In the case of zeolites, HCPL adsorption isotherm followed an L-2 pattern, typical of monolayer adsorption, being the Sips model the one which better describes the adsorption of gallium onto the zeolite.

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The use of dialogues, role plays, songs, and poetry in teaching speaking has become common in English‐language teaching. These language‐learning activities are very popular among language teachers and with language learners. Over the years, these activities have become even more prevalent as communicative language teaching (CLT) has gained popularity. In response to the CLT methodological change, teachers and materials developers have used these activities to focus on different ways of providing students with meaningful input, useful materials, and interesting content to engage learners in “real” communication and enjoyable uses of the target language in classroom contexts. In this entry, I will explain how each of these activity types can make a positive contribution to language learning and then offer some suggestions for classroom implementation.