About ITestYou is an adaptive education platform for Math, English Vocabulary, Foreign Languages and other subjects. Whether you are already A+ student or just want to become one -- practicing online with us is more fun than ever!

It was started by Pavel Simakov in 2005 when his younger son was just 10. Pavel was frustrated by xeroxed math worksheets in the middle school and developed ITestYou to help his son study. We worked on this together over the years including writing this data mining article about SAT vocabulary. At the peak popularity, we had over 50K regular mobile apps users.

In 2018, the site was shut down as Khan Academy and fulfilled the vision. All source code and the content are posted on Github.

Below are few examples of the student experience:

One of the key design goals was to support efficient localization (L10N) and internationalization (I18N) of learning objects. In this article I explain in detail how this is accomplished.

Here is a quick example of a math problem that renders in English and Russian:

	<?xml version="1.0" encoding="UTF-8"?>



		bindings="{a,b,c}" defaults="{32,4,7}"



			   Joan needs $${b*c+a} for a class trip. She has $${a}.

			   She can earn $${b} an hour mowing lawns.

			   If the equation shows this relationship,

			   how many hours must Joan work to have the money she needs?






			  ${c} hours



			  ${c+10} hours



			  ${b*c} hours



			  ${b*c-b} hours