Sitepoint.com – Master JavaScript Closures Data Structures and Map Reduce

If you’ve taken an introductory JavaScript course, or you have a little bit of experience with JavaScript or another programming language, this course can take your skills to the next level This course focuses on the tools and techniques you need to understand to be effective and productive working on JavaScript in the real world
Get firmly grounded in the fundamentals of intermediate JavaScript with an eye to the future of this remarkable and evolving language
Once you have found your footing with JavaScript, move onto ES6 with our course Diving into ES2015. If you’d like a different challenge, why not try Functional JavaScript Programming