1. APPLICATION OF A TEACHING STRATEGY FOR THE UNDERSTANDING OF GEOMETRICAL OPTICS IN OPTICAL INSTRUMENTS AT SECONDARY-SCHOOL LEVEL Gustavo Rodríguez Morales 1, Juan C. Ruiz Mendoza 2, Nivia Álvarez Aguilar 1 1 Facultad de Ingeniería Mecánica y Eléctrica, UANL 2 Facultad de Ciencias Físico Matemáticas, UANL México 1

2. Abstract The study of physical phenomena is always a hard task for students and in many cases for the teachers to transmit the correct concept when it is based on misconception of the theme. This fact always induces a lack of attention in the student and consequently a decrease in interest in any science theme, this, to avoid frustration about its performance on those topics. This kind of attitudes moves the student to use other ways to obtain an approval grading without being conscious of the benefits that science topics can give him for future studies or in every day reasoning. In this work we choose to study the theme of geometrical optics in optical instruments in order to reinforce or change the previous conception of these instruments by the teachers. A starting survey were conducted about the working nature of optical instruments such as microscopes, cameras and telescopes. survey results reflect a low understanding or total ignorance of the optics working principles. A didactic strategy was applied where in a sole activity the student can: observe, model, interact, interpret, describe and argue about the physical phenomenon. This applied to a group of teacher. The exit survey shows that teachers present a tendency to skill development, an increment on critical reflection and auto-criticism. Teachers, reflect, valued and use the acquired knowledge, linking it with activities and practical situations of everyday life and in its context. 2

3. Familiarity with optical instruments Teachers and students shows a high unfamiliarity with optical instruments 3

4. Essential vias Observation of the physical phenomenon is perceived by actual contact with the studied phenomenon. Modelling: Through her students make and solve problems from the observed and experimented with the use of software designed for the purpose. Experimentation: problem situations derived from observation are verified. 4

5. Didactic material 5

6. Organizational aspects A group of 20 secondary school physics teachers in a 10-hour course. A classroom was conditioned with 20 computer with software installed. A laboratory with ten experimental equipment to form teams of two teachers for the experimentation. 6

7. Observation Stage 1. Observation with the refractive telescope A refractor telescope was shown and are instructed to observe distant objects and to talk about the operation of the instrument. They are asked to explain their operation. The preconceptions as the starting point for the implementation of the strategy in order to achieve a conceptual change 7

8. The observation Geometrical optics equipment 8

9. Hands on geometrical optics 9

10. Observation Experimentation with one lens, convergent and divergent cases 10

11. Observation Experimentation with combination of two lenses. 11

12. Problemic situation Construction of a refractive telescope 12

13. Modelling Stage 2. Modelling the lenses 13

14. Modelling Telescope design 14

15. Integral strategy In this way the didactic strategy was applied by the three vias, media and methods: Experimentation Observation Modelling In order to study the physical phenomenon in an integral way. 15

16. Evaluation of the implementation Evaluation of the partial implementation of the strategy results Once the strategy was applied positive results were observed, the most significant are: Teachers take on a leading role in the development of their activities. Comments during activities show teachers with a tendency to develop skills and their ability and an improvement of its critical reflection and of the self-criticism. By using various media and resources, allowed to concrete the process in an integrative way. Working observation and interpretation in a interrelated manner gradually allowed the development of an interpretive logic. 16

17. Conclusion The implementation of the strategy corroborated that the way to implement the Geometrical Optics theme was positive because teachers gain a high domain of it, verified by preparing teachers to apply knowledge in practice. The level of motivation shown by teachers and the good results when using different media, allow them understand optical phenomena in its entirety. The designed strategy constitutes an alternative route, that allows an orientation for the teacher about how can he concrete, in practice, instructional and educational activities that enhance the integral education of their students. 17

18. Thank you! 18

19. References Elizondo M. (2013). Dificultades en el proceso enseñanza aprendizaje de la física. Año 3 No. 5 Enero- Junio 2013. pp. 70-77. Estrada, C. (s.f). Reflexiones sobre la problemática en el aprendizaje de las ciencias. Conf. memories available in: dcb.fi-c.unam.mx/Eventos/Foro3/Memorias/Ponencia_36.pdfdcb.fi-c.unam.mx/Eventos/Foro3/Memorias/Ponencia_36.pdf Guía docente de aprendizaje de las ciencias. Universidad de Alcalá. Máster en Formación del profesorado. Curso 2010-2011. Disponible en:www2.uah.es/jmc/asigaprendizaje.pdfwww2.uah.es/jmc/asigaprendizaje.pdf Ruiz, J C.( 2005), Alternative methodology for the training of students from the teaching- learning process of physics, Report doctoral thesis in Education, Universidad de Camagüey, Cuba. Ruiz, J. C., Formación integral del estudiante mediante la dinámica totalizadora del proceso de enseñanza aprendizaje de la Física. Revista cubana de Educación Superior.XXVII.ISSN:0257- 4314, mayo- agosto Cuba, (2007), pp.33-43. Rodríguez, G., Ruiz, J. C.(2012), Construcción de software de Óptica Geométrica, Facultad de Ciencias - Físico Matemáticas de la Universidad Autónoma de Nuevo León, Monterrey. 19