To learn Haskell I work through CIS 194 - Spring 2013 by Brent Yorgey, as recommended in https://github.com/bitemyapp/learnhaskell.
The author of the second link provides good reasons why he recommends this course here: http://bitemyapp.com/posts/2014-12-31-functional-education.html
Before, I have read Learn You a Haskell, which lacks practice problems, and that's why I follow CIS 194 course.
To check my solutions, I looked at https://github.com/bschwb/cis194-solutions for reference.