Learn English has quite a few good, thematic, Crossword Puzzles that are accessible to Intermediate English Language Learners.
They have a number of other language games on the same site if you scroll down. I had a hard time really getting how some of them are played, though. One nice thing they did have was they had embedded a couple of popular, and well-designed, word games, Thesaurus Scramble and Topic Tangle. The only place I’ve seen these games, or copycat versions, have been on online arcade-like sites that are usually blocked by School District filters. They might slip past the filters being embedded this way.