From rockets to stock markets, many of humanity's most thrilling creations are powered by math. So why do kids lose interest in it? Conrad Wolfram says the part of math we teach — calculation by hand — isn't just tedious, it's mostly irrelevant to real mathematics and the real world. He presents his radical idea: teaching kids math through computer programming.

Education scientist Sugata Mitra tackles one of the greatest problems of education — the best teachers and schools don't exist where they're needed most. In a series of real-life experiments from New Delhi to South Africa to Italy, he gave kids self-supervised access to the web and saw results that could revolutionize how we think about teaching.

Our lives, our cultures, are composed of many overlapping stories. Novelist Chimamanda Adichie tells the story of how she found her authentic cultural voice — and warns that if we hear only a single story about another person or country, we risk a critical misunderstanding.

Western countries throw out nearly half of their food, not because it’s inedible — but because it doesn’t look appealing. Tristram Stuart delves into the shocking data of wasted food, calling for a more responsible use of global resources.

Less than 10% of plastic trash is recycled — compared to almost 90% of metals — because of the massively complicated problem of finding and sorting the different kinds. Frustrated by this waste, Mike Biddle has developed a cheap and incredibly energy efficient plant that can, and does, recycle any kind of plastic.

New York City residents produce 11,000 tons of garbage every day. Every day! This astonishing statistic is just one of the reasons Robin Nagle started a research project with the city's Department of Sanitation. She walked the routes, operated mechanical brooms, even drove a garbage truck herself—all so she could answer a simple-sounding but complicated question: who cleans up after us?

Kevin Allocca is YouTube's trends manager, and he has deep thoughts about silly web video. In this talk from TEDYouth, he shares the 4 reasons a video goes viral.

Use The Compleat Lexical Tutor to practise English with learning materials covering vocabulary, grammar and everyday language.

The Internet Grammar of English is an online course in English grammar written primarily for university undergraduates. However, we hope that it will be useful to everyone who is interested in the English language. IGE does not assume any prior knowledge of grammar.

The Story of Electronics explores the high-tech revolution's collateral damage—25 million tons of e-waste and counting, poisoned workers and a public left holding the bill. Host Annie Leonard takes viewers from the mines and factories where our gadgets begin to the horrific backyard recycling shops in China where many end up. The film concludes with a call for a green 'race to the top' where designers compete to make long-lasting, toxic-free products that are fully and easily recyclable.

Use Using English for Academic Purposes to practise English with learning materials covering vocabulary, grammar and everyday language.

Use Vocabulary.com to look up English words, check meanings and support vocabulary learning.

Use Wordnik to look up English words, check meanings and support vocabulary learning.

Use Writing Center to support your English study: a guide to the process of writing.