Another possibility is:
https://www.codecademy.com/learn
Codecadamy generally does an excellent job teaching programming languages. They just released a Java course, which I have not personally tried yet, but I trust it will be good. Codecadamy also has an excellent Python course (which I used when I was first learning the language). Python is a much simpler way to get an introduction basic programming concepts, it makes a good first language. After having the students learn how variables, data types, functions, loops etc. work in Python, it will be easier for them to pick up Java and OO concepts.