Course on Hyperledger, enterprise grade blockchain https://www.edx.org/course/blockchain-business-introduction-...

Course on cryptocurrency: https://www.coursera.org/learn/cryptocurrency

I have taken both, the coursera course actually walks thru some other data structures needed to build a blockchain, and points you in the direction of more heavy math if you want to go there.

Both of courses are solid introduction to blockchain tech. And best of all they are both free. :)