what is a wormhole?

Wormholes are solutions to the Einstein field equations for gravity that act as "tunnels," connecting points in space-time in such a way that the trip between the points through the wormhole could take much less time than the trip through normal space.

The first wormhole-like solutions were found by studying the mathematical solution for black holes. There it was found that the solution lent itself to an extension whose geometric interpretation was that of two copies of the black hole geometry connected by a "throat" (known as an Einstein-Rosen bridge). The throat is a dynamical object attached to the two holes that pinches off extremely quickly into a narrow link between them.

This analysis forces one to consider situations...where there is a net flux of lines of force through what topologists would call a handle of the multiply-connected space and what physicists might perhaps be excused for more vividly terming a ‘wormhole’.

John Wheeler in Annals of Physics

Note to Visitors

The content viewed in this blog is a collection of various articles & newsletters and is placed only for educational purpose.

Sunday, October 9, 2011

Portfolio Assessment Guide

One form of authentic assessment being widely adapted in schools today is portfolio assessment. Diane Hart defines a portfolio as "a container that holds evidence of an individual's skills, ideas, interests, and accomplishments." The ultimate aim in the use of portfolios is to develop independent, self-directed learners. Long-term portfolios provide a more accurate picture of students' specific achievements and progress and the areas of needed attention.

Portfolios make it easier to develop grading schemes that emphasize assessing individual student growth rather than competition with other students. As self-evaluation is an integral part of portfolio assessment, a highly competitive climate will prove counterproductive. Students will be reluctant to focus upon their deficiencies if they believe it will put them at a disadvantage in the competition for the top grades. Often portfolios are used to supplement, not replace, traditional assessment procedures.

Remember, portfolios should be developed by the students, not the teacher. Students should have freedom in selecting items to include in their portfolios. It is advantageous to make the whole portfolio process a collaborative teacher-student effort, with the teacher becoming more of a consultant to the student. The teacher functions more as a coach than a director. Any item that provides evidence of a student's achievement and growth can be included in a portfolio. Commonly used items include:

Examples of written work Journals and logs Standardized inventories Videotapes of student performances Audiotapes of presentations Mind maps and notes Group reports Tests and quizzes Charts, graphs Lists of books read Questionnaire results Peer reviews Self-evaluations

Each item in the portfolio should be dated to facilitate the evaluation of progress through the year.

Typically, teachers hold periodic individual conferences with their students to review their portfolios. During this interview it is important to listen to the students' assessments of the items in their portfolio. The focus of the discussion should be upon the products included in the portfolio. The teacher and student work together to set a limited number of objectives for future work. Strive to achieve a dialogue, not a lecture.

Much of the value of portfolios derives from the students' reflection on which items are worth including in their portfolios.

The portfolios may be kept in folders, file boxes, assigned drawers, or other appropriate containers.

Whatever the storage container, it must be readily accessible to the students.

Portfolios are especially helpful at parent conferences. Help the parent examine the portfolio, pointing out evidence of progress and areas of needed improvement.

Be patient. Portfolios are a new concept to most students and parents. There is a learning curve involved in adapting to the process. Experiment to determine what works and feel free to modify as needed.

In some schools students' portfolios are made available to their teachers the following year to aid in diagnosis. A few schools are experimenting with the development of a permanent portfolio that follows the students throughout their total school experience. (This would be separate from their cumulative record folder.) Upon graduation the students would keep their portfolios.

Develop your own teaching portfolio as a means of facilitating your professional development. It also can prove invaluable in tenure assessments and future job searches. Your professional portfolio might include videotapes of successful classes, curriculum materials you have developed, course syllabi, sample lesson plans, professional development goals and objectives, workshop classes attended, publications written, student evaluations, awards, certificates, professional affiliations, principal's and supervisor's evaluations, and your teaching philosophy.

A large three-ring binder is a practical way to organize your portfolio. Use tabs to indicate the various categories. You might occasionally share your portfolio with students to model the processes you are urging them to follow.

Hart, D. (1994).Authentic Assessment: A Handbook for Educators. Menlo Park, CA; Addison-Wesley Pub. Co.

Excerpted fromClassroom Teacher's Survival Guide.

No comments:

Post a Comment

Collection of Books on Teaching Methods

Popular Posts