Asbel Lopez [*]
Teachers must prepare not only future scientists, but also citizens who will confront unprecedented technological and ethical challenges in their lifetime
I When Mexican teacher Jose Antonio Lopez Tercero was a student, he regarded as quite plausible the idea that velocity and potential energy are like two machines that can be stored in a cupboard. Back in those days, he was led to believe all kinds of outlandish things. His innocence was caused not by reading Gabriel Garcia Marquez's magic realist novels, but by dozing through abstract physics classes. "They were awful," recalls Lopez Tercero, who now teaches chemistry at the Escuela del Sur Institute, a secondary school in Mexico City.
Today he tries to teach science in the way he would liked to have learnt it. As often as possible, he uses everyday objects to help his students grasp abstract concepts. A washing machine can illustrate dispersion by centrifugal force; clothes show how to distinguish natural and synthetic fibres; plastics aid the study of oil derivatives; lemon juice and red cabbage bring acids to life, while television helps explain how electromagnetic waves work.
This approach represents a huge qualitative change, at least in comparison to what Lopez Tercero had to go through as a pupil. Back at secondary school, he remembers that "the teacher would arrive, announce a concept, write down a formula, and teach us how to solve problems using the latter. All I did was work through the formulas by replacing letters with numbers."
This traditional teaching method, based on the transmission of a body of knowledge and the study of problems with little relevance to many students, is still practiced, and not just in Mexico. According to Jacob Bregman, a specialist in science education at the World Bank, "science education in developing countries often relies too much on memorization of facts and not enough on learning to understand the relevance of knowledge and its application in the local context." In the industrialized countries there is much greater emphasis on the problemsolving approach, decision-making, and developing the ability to analyze and work in a team.
Failings in the educational systems of Third World countries are particularly alarming because economic development is increasingly linked to scientific and technological knowledge. But there is now a widespread desire for change, reflected in a wave of reforms in scientific education that have taken place around the world in the last few years.  And though the reforms differ from country to country, they have certain common features.
One of them is relating science to everyday life, as Lopez Tercero does in Mexico. As well as improving the learning process, this method makes students more enthusiastic and genuinely interested in science. In recent years, half of the graduates from the Escuela del Sur Institute have embarked on scientific careers, 30 per cent more than the Mexican school average.
Unearthing the practical end of knowledge
Relating science to everyday life also means anchoring teaching more firmly in the local context. Using problems that affect the community, teachers endeavour to show the practical value of scientific knowledge in determining the causes of specific phenomena. They encourage students to come up with ways of possibly preventing environmental catastrophes.
Teachers are making "huge efforts in their classes to treat problems which are relevant to the students instead of using abstract examples from textbooks," says Bettina Walther, the co-ordinator of a science education project in Tanzania's secondary schools. Launched in 1997, the project involves maths teachers from 27 schools, who focus lessons on development projects in the towns where they teach. For example, geometry courses might be based on the practical case of installing electricity and telephone lines to explain concepts while applied maths lessons look to using fertilizers and pesticides for learning various operations. …