Japanese 2 Level 7: words for tea
I think it would be important to differentiate between おちゃ and こうちゃ; students learnt おちゃ as tea in Japanese 1, only to be told that こうちゃ is tea in Japanese 2 with no explanation as to why they are different. Listing them as green tea and black tea, respectively, would negate a lot of confusion.
(Perhaps also differentiate between ちゅうもん and ごちゅうもん.)