Recently, I got my Project Management Professional (PMP) certification. Now, I am on the hunt to get PDUs (continuing education credits) to renew in the next couple of years. So, a friend sent me a list of potentials that are FREE.
Check out these sites for 40 free PMI PDUs:
Six Sigma Yellow Belt: http://6sigmastudy.com/Six-Sigma-Yellow-Belt.asp
Scrum Fundamentals Certified: https://www.scrumstudy.com/certification/scrum-fundamentals-certified
Digital Marketing Associate and Marketing Strategy Associate: http://smstudy.com/freeresources/earn-4-free-certifications