Johns Hopkins University, School of Public Health (JHUSPH) offers a free course in R programming that starts today. I took this online course in 2013 and found it very useful. I highly recommend it for anyone wanting to learn R for any type of statistical analyses. A few of my assignments are posted here in this blog (linked from ‘R’ and ‘Coursera’ topics on the right side panel). My code can be found here: https://github.com/ljcohen/R_Computing_for_Data_Analaysis
JHUSPH also offers a Data Science Specialization through Coursera for a small fee and requires a series of 9 related courses plus a capstone project related to data science visualization, and statistics. Seems like a good option for those not enrolled in a University and wishing to develop these skills towards a certification.
The individual courses are still free without certification.