Arvind Gupta, 67, is a toy scientist whose life’s work has been to introduce students and teachers across the country to do-it-yourself toys and science models fashioned out of discarded or low-cost material. Gupta was awarded the Padma Shri in 2018, for his unique contribution to education. His website arvindguptatoys.com contains thousands of free “recipes” to make toys from broken CDs, used cartons, straws, cardboard or matchsticks. His favourite is the Flapping Ear Rabbit made from a square piece of paper in less than 30 seconds. “It always brings a smile to a child’s face,” he says.