Most classes will sit in rows, which is perfect for making teams. Split the board into columns, one for each row of students. Write 1-10 in each column. The students race to write 10 words for a given category (eg: animals, school subjects, food etc). If they are good students you can forbid not only repeats of words in their own column, but in the other teams' too.
A different version of this is "shiritori". Write one word for each row at the top of the column. The first person has to write a word that begins with the last letter of the one above. For example pen -> net -> ten -> nice etc. The students will know this game in Japanese.
See more information about how to get started at the Central Wikia tutorial.