For advanced classes this will be quite easy and go quickly. You can easily put part one and two together for them. For the others, it's a wonderful two-parter to keep you doing less lesson planning

Part 1
Give the handout to all students.
Now all students in the class stand up. Explain that they will each take turns reading off the pairs of words (do the first yourself). If they're correct, they remain standing. If they're not (I give multiple tries) they sit down and the next person must try the same word. Repeat until all 30 word pairs have been read. I do the last one also, since no one has yet been able to do Really vs. Leery haha
Everyone still standing gets a candy
Now they work together to write the Korean translation of the English words. This is just good review, since most of these words are things they should know by now, and the rest are ones that are just fun to learn. (You'll have to go over the meaning of some... for example, I translated "Sh*t" as simply "poo" (as far as I know, there's no swear equivalent which has the same literal meaning), so you must explain that in English this is a strong word and some people may not like it.
...Or you may want to change some of my words. I geared this for highschool boys would love to use the word "sh*tty" in their everyday language...but maybe not so great to teach younger kids.
Give some time, then take up together. I've included an answer sheet. I used this as a wonderful opportunity to study my own Korean vocab, or you could simply print it off onto a piece of acetate and use an overhead projector.
ALl this will take about 40 mins for a low-level class, 20 mins for an advanced class
Part 2
(Using one of Capebretonians ideas for pronunciation would really help as an intro to this!)
Rhyming! Go over the basics of what rhyme is, and how it's determined. It is the last vowel-consonnant sound of a word (NOT the spelling). For example:
Greet: "eet" --> eat, meat, meet, sheet (NOT sh*t), feet, beat,
Great: Though spelt with "ea" like meat, eat, and beat, is NOT the same SOUND.
Night: "ight" (아이트) remind them this is ONE syllable in English...
light, bright, fight, might, tight, bite, white,
(point out again the spelling difference, but same sound of "white")
"eight", though spelt the same is NOT a rhyme (에이트)
Now give each ground a numbered sheet of paper. Write an easily rhymable word on the board and give them whatever-amount-of-time (I did 90 seconds). Take the sheets away and mark them. Show points on the board, and go over mistakes and impressive rhymes one might not come up with right away.
Repeat until the kids are bored. hahaha, I found they rather enjoyed this activity, because even the advanced classes seemed to often be guessing. They couldn't seem to quite grasp the same-sound-ness of some words, and thusly I think they were often shooting in the dark... strange how they really enjoyed it. Also the advanced classes have a bigger vocab to draw from and will want more time. Lower levels really don't need much time because they exhaust their vocabularies fairly fast.