'Okayama-ben' is the dialect of Japanese spoken in Okayama prefecture.
It is considered a 'rough' dialect by most people outside of Okayama, and most people from Okayama would be embarrassed to speak Okayama-ben outside of Okayama. That being said, if you drop some Okayama-ben around your co-workers, they will often be amazed and surprised.

Okayama dialect
Standard Japanese
Meaning
Achi あち
Atsui あつい
Hot
Attakee あったけえ
Atatakai あたたかい
Warm/mild/
Bokkee ぼっけえ
Totemo とても
Very
Choudee ちょうでえ
Choudaiちょうだい
Please/Give me~.
Deekon でえこん
Daikon だいこん
White radish
Deeree でえれえ
Totemo とても
Very
Gyousan ぎょうさん
Takusan たくさん
Many/A lot.
Ja じゃ
Hai はい
Yes/Roll call
Jarou じゃろう
Darou/Deshou だろう・でしょう
Isn't it/Don't you think/Right?
Karee かれえ
Karai からい
Spicy
Oen おえん
Dame だめ
Not good.
Miteru みてる
Nakunaru なくなる
To die/run out.
Nanbo なんぼ
Ikura いくら
How much?
Nani shon? なに しょん?
Nani o shiteiru no desuka?
なにを している の ですか?
What are you doing?
Nukii ぬきい
Atatakai あたたかい
Warm/mild.
Oidensee おいでんせえ
Irrashaimase いっらしゃいませ
Welcome (to a shop)
Sabi さび
Samui さむい
Cold
Sou ja naa そうじゃなあ
Sou ja そうじゃ
Sou da そうだ
Sou desu そうです
Yes, it is./Right.
Sugee すげえ
Sugoi すごい
Amazing/great
Yabee やべえ
Yabai やばい
Amazing/terrible(general surprise)
Yashii やしい
Yasui 安い・やすい
Cheap

Common slang/words your students will use
Slang
Standard Japanese
Meaning
Chou ちょう
Totemo とても
Very
Chari ちゃりCharinko ちゃりんこ
Jitensha じてんしゃ
Biycle
Hidoi ひどい
-
Unfair/mean
Honma ホンマ
Hontou ni ほんとうに
Really/seriously
Ikemen イケメン
-
Cool guy/good looking guy
Kakkoi かっこい
-
Cool (also used as a compliment for boys)
Kawaii かわいい
-
Cute (also used as a compliment for girls)
Maji (de)  まじ(で)
-
No way!/Seriously?/Really?
Meccha めっちゃ
Totemo とても
Very
Mendoukusai めんどうくさい
-
Annoying
Mukatsuku むかつく
-
Pissed off
Muri 無理(むり)
Dekinai/Dekimasen できない
Impossible. Can't do it.
To which you respond, Muri janai! むりじゃない
Saiko さいこ
-
Best/Number 1/Awesome.
Saiyaku さいやく
-
Disastrous/Awful.
Uso うそ
-
Lie/Liar
Wakaran/Wakkanai わからん・わっかない
Wakaranai/Wakarimasen わからない
Don't know/Don't understand
Yabai やばい
Yabai means inconvenient/dangerous.
Amazing/terrible(general surprise)
Yada やだ
-
Yuck/undesirable