A quick search of the Internet will reveal hundreds of free crossword puzzles and other word games. Another adding the word "maker" or "builder" to the same search will return many free programs for building your own crossword puzzles. The problem with about half of those results is those websites have pop-up ads or are otherwise littered with obtrusive advertising. The following are five crossword puzzle builders that offer simple and effective user interfaces without obtrusive advertising.
1. Read, Write, Think offers a crossword puzzle builder as well as pre-made crossword puzzles designed for all grade levels K-12.
2. Just Crosswords has a new puzzle maker with which you can build crossword puzzles, save them, print them, or embed into your website or blog. Just Crosswords also has more than 300 categorized, educational crossword puzzles.
3. Variety Games hosts a free crossword puzzle maker. You can select the dimensions of your puzzle or allow your puzzle to be auto-formatted. To use the puzzle in your classroom you will have to print the puzzle.
4. Armored Penguin has a very flexible crossword puzzle builder. You can select from a simple puzzle maker or large puzzle maker depending on the number of clues that you want to include. Armored Penguin's program also gives you the option of including or excluding an answer key.
5. Ed Helper has a basic crossword builder that accepts up to thirty words. Ed Helper has other basic puzzle builders for free. To use the more advanced options, like larger puzzles, you will have to subscribe to the service.