For the cheesy popcorn:
1) Pop the popcorn according to package instructions.
2) While hot, carefully open package and dump into a large bowl. Drizzle oil over the popcorn, and toss the popcorn with your hands to coat. Add the cheese and toss again. Season, to taste, with salt. Cool. Transfer to a sealed container and tuck in a lunch box.
For the sweet and spicy popcorn:
1) Put the sugar, butter, and chilli powder in a microwave-safe bowl; microwave on medium (50 percent power) until butter melts, about 1 minute.
2) Stir to dissolve sugar. Drizzle over freshly popped popcorn; and toss to coat evenly. Cool. Transfer to a sealed container and tuck in a lunch box.
For the rocky road popcorn:
1) While it's still hot, carefully open and dump popcorn into a large bowl. Add the chocolate chips and marshmallows.
2) Return popcorn to the microwave. Cook on high until the chocolate chips and marshmallows become gooey, about 1 minute. Add the peanuts, if desired, and toss with a spoon until all the popcorn is coated.
3) Cool until chocolate hardens, about 20 minutes. Transfer to a sealed container and tuck in a lunch box.