Readings & Meanings:
My final exam was the top in my class.
I'm getting in touch with other graduates in the same class as me.
The treatment of the patient with the last stages of cancer was successful.
月 is the radical, and here it is definitely derived from the moon kanji.
其 is the phonetic, and it means "that" now but originally was the pictograph of a square device for winnowing grain, plus a desk.
Square/rectangular and moon leads to the idea of a period or cycle, as in the fixed phases of the moon.