Treehouse is my code learning platform of choice. There are other online training solutions available like Pluralsight, Infinite Skills, Codecademy and Lynda.com, but I liked Treehouse better because their gamification keeps me motivated to learn more. You earn more points and achievements the further along you go.
Treehouse has a nice UI and slight gamification which lets you score points in different skill sets and collect achievement badges.
Overall, I highly recommend Treehouse. They’ve been a huge help for me, the courses are enjoyable.