SpellingCity is a wonderful site for educators to help students learn Vocabulary & Spelling. This is done by creating word lists and integrating them into learning games. Also, SC has an educational portal and for a paid membership teachers can create student accounts w/out needing a student email address (ideal for CIPA/COPPA compliance).
There is also a free iOS app which integrates flawlessly w/ SC's site, click here.
I highly recommend checking out SpellingCity by clicking here!!
*SpellingCity is a paid subscriber of Technology Tidbits.