Comment about tic-tac-toe games

Tic-Tac-Toe games are a very interesting way for teachers, teach english their students.
The students are playing and, in the same time they are learning.
I think that is OK to teach grammar in games, it's a very good way to teach grammar, because the Students love the games, and they would enjoy a lot.
Another way to teach conditionals could be in puzzles or games with clues, it could be more attractive than a common class.