Take your front end skills to the next level with critical skills and pick up your first real programming language: JavaScript. Learn how to make your website interactive, look good on any device, and best practices around development. The next natural step after front end basics and the perfect track for designers.
(www.codecademy.com)
Learn the basics of JavaScript and programming languages generally through these interactive tutorials. Pay close attention to this lesson since it will lay the foundation for many other lessons in the future. Go through the whole course.
(juliepagano.com)
Learning how to find errors in your JavaScript is a fundamental skill to being productive in the language. Learn the tools you'll need and how to manage your workflow when coding in JavaScript for your website.
(github.com)
JavaScript is notorious for its quirks and it oftentimes leads to surprising and sometimes unsightly code. This is the canonical book to read on JavaScript. If you want true mastery of the language, read this thoroughly and take its lessons to heart as best you can.
(html5boilerplate.com)
This boiler plate is for you to download and really get things up and running quickly. It helps smooth out CSS differences between browsers, manage your file directory, and even give you some pre-built HTML. Download it, explore it, and use it for your next project.
(www.youtube.com)
Bootstrap is a library that makes you more productive when you're building websites. It has a lot of CSS classes that you can add to your HTML to make your website work on different devices, look nicer, and have more functionality. Watch this tutorial on how to use it.
(css-tricks.com)
JavaScript gives you access to something known as the Document Object Model, or DOM. jQuery gives you even easier access to it. Learn what it is in this short article.
(try.jquery.com)
Pick up the essential tools you'll need from jQuery and learn how it's used in your website. Go through this whole course.
(verekia.com)
Now that you understand how programming languages work, you can start applying those ideas to the other technologies you know already. Read this great article by Verekia on Less.