Arvind Gupta, a scientist turned toymaker in India, has designed hundreds of science based toys for
children. For example, a well-known toy phone can be made from paper cups, a straw flute showing
how sound is produced, a balloon car or a spinning straw that works on Newton’s third law of motion,
a fountain from plastic bottle and straws working on air and water pressures, a periscope form pencil
box showing reflection of light, a simple DC motor and so on. In the present methodology, children are
not instructed to make the toy models, but are allowed to do it independently through books/manuals
gradually putting their own ideas. Rather teaching or motivating thinking as in a constructivist
perspective, it helps learning through the natural thinking that occurs when one faces a problem.
Making models is a process of working and reworking to make it better and better. Solving of
problems in tasks asks to understand various science concepts in a conscious way. For eg: a balloon
car may not run due to reasons like no smooth air flow, that help to discover that air provides the push
that can further be framed in an organized way. It also asks to think on friction, surface-tension of
balloon, behavior of air, pressure, effect of mass, etc. in order to make it better/faster. A single toy can
cover concepts that are otherwise taught in separate lessons throughout the year. Problem-solving
thus can be one of the important methods for science learning. Children use chart, write down
problems, reasons, solutions, that reflect on the science learning taking place. Books on science then
become meaningful and useful that finally structures their thinking. It helps cognitive development of
children and solves many of the pedagogic problems such as application of knowledge, integration of
theory and practice, etc. It is a process from experiencing to organized form of knowledge, rather
finding a method to provide the organized knowledge.