Easy SQL Tutorial
SQL Tutorial - Learn SQL Query Programming Language
SQL Injection Tutorial: Learn About Injection Attacks, Vulnerabilities and How to Prevent SQL Injections
Tutorials and Interview questions for Java, data structures, algorithms, programming, coding, FIX Protocol, Tibco RV, UNIX,SQL,books,certifications.
SQLzoo, teach kids programming. I have never used this, looks good for secondary.
SQL Services Tutorial