If there is one kanji you’re likely to see around April, it would be “新” (shin/ atara[shii]/ara[ta]/nii), which means “new.”
April brings the start of a 新学期 (shin-gakki, new school year) and 新年度 (shin-nendo, new fiscal year) in Japan, and 新入生 (shin-nyūsei, freshmen), 新社会人 (shin-shakaijin, new working adults) and 新卒 (shinsotsu, new graduates) start their new semesters and jobs.
Among the ranks of 新社会人 at your company, you may notice some other new faces. 新入社員 (Shin-nyūshain, New employees) differ from their sometimes younger counterparts in that they include those who are mid-career or changing professions. After arriving in their new place of work, they’ll have to adjust to the new 社風 (shafū, corporate culture).