I got this game from another ALT in my city, but I wanted to share it because it's good.
Break up students into groups (4ish people).
Have students take out lined paper and their picture dictionaries
Assigning writing/presenting order within each group via rock paper scissors (or by seating arrangement).
Have the ALT call out a letter. (E.g. "B")
1st writing representative student must write five words that start with that letter. (Students will use their picture dictionary for this) Other group members are to provide support (finding words, spell checking, and teaching pronunciation).
Representative student will go to ALT once finished writing. Representative students remain at the front of the room.
ALT will check spelling of each group. Each word will get awarded points. Misspelled words get 0 points.
Wait until every group representative comes up and spellings are checked. Once spelling has been checked, each representative student will present their words.
If other groups have written the same word, the representative will raise their hands and say "Me, too!" One point is rewarded for each word that other groups have as well. If no other group has written the word, then two points are awarded. The homeroom teacher should tally the score.
After all representative have finished presenting, you can either announce a winner and give stickers OR announce the next letter and continue the game with a different representative of each group writing words. Ideally you would do this so that each person in a group can practice writing. However will take time, so you can have the students keep their papers, write the names of the group members on the paper, and then you can pick up the game when you have time at the end of class in the future. If you need to kill a lot of time then this game is great.
Please comment with any questions, concerns, or suggestions for improving this activity.