Plant Tycoon and Risk are two games that recently have had online versions become available.
Plant Tycoon would be a good language-learning exercise related to gardening, particularly its tutorial. Risk would be an enjoyable activity for English Language Learners who are learning about World War I and/or World War II. An added benefit is that it has audio support for some of its text.
I’ve placed links to both on my website under Word and Video Games.