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What do Bill Gates, a pop singer and a wrestler all have in common?!

Our friends in Brazil, the Lemann Foundation, recently asked some twenty celebrities about their favorite way to learn math, and they shared some really touching thoughts about Khan Academy and why they love using it. We thought it would be fun to share them with you, too.

Bill Gates, for instance, stressed the fact that Khan Academy is a great tool for one`s learning adventure, saying that the “breath of stuff is incredible and the explanations are clear”. He also pointed out that he uses Khan Academy to remind himself about certain concepts and with his kids “when things are complicated for them” - which makes us feel better about forgetting things, too!

This year, over two million Brazilians used Khan Academy to study and learn - we’re so excited that they’re enjoying the Portuguese site.

Em diante!


O que Bill Gates, Anitta e Anderson Silva têm em comum?

A equipe responsável pela Khan Academy no Brasil recentemente perguntou para mais de 20 celebridades do mundo da música, das artes e do entretenimento sobre sua maneira favorita de estudar matemática e eles compartilharam os benefícios de estudar com a Khan Academy de forma gratuita e empolgante. O grupo inclui ídolos nacionais e internacionais, como Bill Gates, a cantora Anitta e o campeão de MMA Anderson Silva. Aqui você pode ver alguns desses vídeos.

O Bill Gates, por exemplo, falou que o site é uma excelente ferramenta na aventura do conhecimento - “a quantidade de conteúdo é incrível, as explicações são simples”. Ele apontou que tem acessado a Khan para se lembrar de alguns conceitos e que seus filhos também usam “quando têm alguma dificuldade” – o que nos faz sentir melhor quanto esquecemos as coisas também!

Esse ano já são mais de dois milhões de brasileiros estudando e aprendendo com a Khan Academy! Estamos super entusiasmados com o sucesso do site no Brasil!


Learn how to make webpages with HTML & CSS on Khan Academy

I often get asked how I got into programming. Well, it all started with me forgetting to buy a gift for my mum. I was in 6th grade, and it was Mother’s Day. We lived a few hours walk from the shops in town, and I had to walk by a high-security penitentiary to get to those shops - given the recent surge in prison escapes, I didn’t feel like taking the risk.

I’d been browsing the web a lot recently, checking out the fan websites for my favorite boy bands and hanging out in pet-themed chat rooms. I always liked the idea of making gifts instead of buying gifts, so I thought “hey, I’ll make my mum a webpage!”


I searched on Yahoo! for instructions (this was even before the days of Google’ing), and made a webpage for my mum with a big cheesy “Happy Mother’s Day” GIF at the top (thanks, Microsoft Word Art!). My mum was happy that I’d taken the effort to learn something new; I was happy that I’d discovered how to get away with never buying gifts and I was left with a newfound curiosity for making things on the web.

And that’s how I got into programming. I started off in HTML and then got into Perl, Java, JavaScript, PHP—anything I could get my hands that would enable me to share creations on the web.

Now, nearly 2 decades later, the web is ubiquitous and there are more than 1 billion websites on the internet. Every single one of those websites is built with HTML, and probably many of them include CSS for styling and JavaScript for interactivity.

That’s why I’m thrilled that we can now teach HTML and CSS on Khan Academy. HTML/CSS is the first step on the path to being a web developer, plus it’s also a skill that non-developers can hugely benefit from - like bloggers, marketers, and librarians - because HTML shows up in so many of their jobs, too.

You can try out our HTML/CSS environment here. It’s interactive and real-time, just like our ProcessingJS environment, plus includes a color picker, image picker, and number scrubbers.


To help you learn how to make webpages, we’ve put together an Intro to HTML/CSS course. It’s around 8 hours of talk-throughs, coding challenges, projects, and quizzes, and will give you a great basis in the most common HTML tags and a wide range of CSS selectors and properties.


For something more bite-sized, you can start with the Hour of Webpages, which is one of our Hour of Code offerings this year.


Thank you to the team for all their hard work in making this possible - John Resig, Brian Bondy, and Alex Rodrigues. Let’s get more people hooked on HTML!


Algorithms on Khan Academy in collaboration with Dartmouth College

What is an algorithm? It’s a sequence of steps that you follow to solve a problem. In everyday life, you might have an algorithm for hanging up your laundry, efficiently going through a shopping list, or finding an empty parking space in a lot. In computer science, an algorithm is a sequence of instructions that a computer program follows. Algorithms form the basis of the most interesting and important programs we use, such as the algorithm that Google uses to calculate driving directions, or the algorithm that Facebook uses to automatically tag you in a photo.

Because algorithms are so important to computer science, they are a core part of a computer science curriculum. The AP CS A class teaches object-oriented programming with algorithms,  every college CS student will have at least one algorithms class and encounter algorithms everywhere, and every software engineer interviewing for a job will review algorithms while they’re prepping for an interview.

Given how important algorithms are, we were elated when Dartmouth professors Thomas Cormen and Devin Balkcom suggested writing an online course on Algorithms, available to anyone for free, forever, on Khan Academy. If you’re a college CS student, you might recognize the name “Cormen” - he’s the “C” in the “CLRS”-authored Algorithms textbook, the most popular algorithms textbook used by college classes. Balkcom is a fellow professor at Dartmouth, and he’s actually rewritten their introductory CS class, so he’s an expert in teaching algorithms to new computer science students.

 We worked over the summer to create an introductory Algorithms class that’s highly interactive. Algorithms can be hard to wrap your head around, so we have both step-by-step diagrams and interactive visualizations to explain each algorithm:


We also want to give you a chance to try coding the algorithms yourself, so we’ve used our JavaScript coding challenge framework to write 19 challenges with unit tests (and you’ll have to write unit tests yourself!):


We’ve also sprinkled in a few quizzes, to make sure you understand concepts like asymptotic and graph notation:


This curriculum covers everything you’d find in an intro course - asymptotic notation, binary search, selection/insertion sort, recursion, merge/quick sort, graph representation, and breadth first search. There’s much more to cover, of course, including going more into how you can design your own algorithms, but we’re so excited about what we have now and how much it could help software engineers in all stages of life that we want to get it in your hands now.

Please dive into the course and let us know what you think - you can leave comments beneath the articles, or email us more detailed feedback at compsci-feedback@khanacademy.org.

Thank you again to Thomas Cormen, Devin Balkcom, and their supporting staff at Dartmouth for making this Algorithms class a possibility.

Posted by Pamela Fox, Khan Academy.



Khan Lab School Opening Day


Back in June we told you that we’d be experimenting with a learning lab, and today marks the opening of the Khan Lab School, which will be composed of a small cohort of around 30 students.

Khan Academy has a history of summer camps and working with classrooms, which have both really helped us better understand opportunities to help teachers and students.

In order to take an even more hands-on and sustained approach, the Khan Lab School will research blended learning and education innovation by creating a working model of Khan Academy’s philosophy of learning in a physical school environment and sharing the learnings garnered with schools and networks around the world.

Our goal is to develop new, personalized practices that center around the student. As this model is developed, we will be sharing and testing the practices in diverse settings to offer new ways of thinking about Khan Academy and the classroom.

The lab school will focus on developing practices that empower students to realize that they can shape the systems and solve problems of the world through their own character, intellect, and passion.

There are already thousands of classrooms across the world that are using Khan Academy. We learn so much from these classrooms and try to share those learnings with other schools and educators. A small-scale lab school helps us further explore how physical environments can be reimagined and blended with online tools to empower teachers and students.

The intent is not just to develop practices, but also to share them in ways most likely to effect broad change. We intend to further share with the world through in-house research fellowships, teacher workshops, videos, publications, and the broader Khan Academy platform.

As this is a research lab school, it is not open for general enrollment at this time. But if you’d like to be on an email list to hear more about the lab school in the coming months, you can sign up here.

- Jason Pittman, Head Teacher, on behalf of the Khan Lab School team


Start your 13.8 billion-year journey with the Big History Project


The Big History Project is now available on Khan Academy. Whether you’re a solo learner or a classroom teacher, get ready to take a self-paced journey through nearly 14 billion years of history in just 10 tutorials!

Big History asks the big questions about our universe, our planet, life and humanity. From the Big Bang to our still-expanding universe, this course, created and maintained by the Big History Project, will lead students on a journey of astounding connections and exciting discoveries. 

The lessons also draw upon the insights of history, chemistry, biology, anthropology, physics, and a variety of other disciplines. Teacher-created lessons include downloadable activities, engaging videos, animations, and articles that bring the voices of leading scholars from around the world to you…and bring history to life.

Today, there’s more information available to us on our phones than was available in all the great libraries of Alexandria, so how do we decide what claims we can trust? Big History guides learners through examining their intuition, looking at the authority, evidence, and logic of claims.

Big History also looks beyond the timeline of human history to explore the connections between distant events billions of years ago and our lives today.

From the massive expanse of the universe to the smallest of atoms, Big History guides you to think across temporal and physical scales.

Both in articles and at the end of each tutorial, students and teachers can access downloadable and printable classroom resources such as lesson transcripts, video transcripts, worksheets and answer keys. Quizzes and glossary challenges allow teachers to assess student comprehension.

Start your journey now!