Tutor
Coach, Private Teacher
noun
This is a combination of the words 家庭 and 教師. A "teacher" who only teaches when you're with your "family" is known as a tutor. They don't teach you at school, they're a private teacher that comes to your home to help you learn.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
家庭教師は、ホワイトボードをかべに立て掛けた。
The tutor put up a white board against the wall.
家庭教師のアルバイトをしています。
I work part time as a private teacher.
日本では拘束時間の短い家庭教師は大学生に人気のあるアルバイトの一つです。
In Japan, tutoring is one of the most popular part-time jobs for college students, due to its short hours.