1. Put the students in groups. Use their regular lunch groups in a class of same-age students, but if you've got a mixed class, it's good to have older kids work with younger ones, in which case you'll need to ensure that the groups have been prepared and agreed upon in advance. If you make the masks in class, be aware that it will take at least 10 to 15 minutes, and many young students will need help with the eyes. As students begin to finish, set up one of your jack-o'-lanterns by a door and have them line up and practice saying "Trick or treat," "Thank you" and "Happy Halloween!" to their homeroom teacher. Set it up by saying, "Look! There's a jack-o'-lantern!" to remind the kids of the key prerequisite to a Halloween visit.

2. When everyone's ready—and ready to listen!—get the homeroom teachers to set out the ground rules in Japanese: The students will go in groups to rooms with jack-o'-lanterns outside, where they will receive candy. There are a total of X number of rooms (knowing this is important so the kids know when they're done!). When they've found all X rooms, they are to return here, where they can compare and trade candy. This is a safety and order issue, and should be 100 percent clear.

3. The homeroom teachers then go off to quickly prepare their own rooms.

4. Call the groups up one at a time. Note your jack-o'-lantern at the door. Each group will "knock" and say "Trick or treat!" and then receive candy from you. They should say "Thank you" and "Happy Halloween!" before going out to search the school for jack-o'-lanterns.

5. Enjoy your brief respite. As each group comes back, remind them of the jack-o'-lantern at your door, and give them more candy on the way back in!

6. It's good to have Halloween music to play in the background as the kids gradually assemble. Interact with the students, counting their candies, asking "What's this?" or what color a candy is, who they got it from, what their favorite flavors are, and so on.

7. When everyone's back, welcome them all "home." Finish with a rousing round of the "Happy Halloween" song, then greet the students as per usual and send them on their way.

Phew! You're done! Don't forget to thank everyone who helped make this all possible!