That instructor is in a different place (city or country) each time we have a lesson together.
I'm always looking forward to finding out where she/he is.
ご質問ありがとうございます。
"That instructor is in a different place (city or country)"＝「その先生は違う場所（街や国）に居ます」
"each time we have a lesson together."＝「私たちのレッスンごとに。」
"I'm always looking forward to finding out where she/he is."＝「いつもどこに彼女・彼がいるのか知るのを楽しみにしています。」
ご参考に。
That teacher is always moving around to different cities and countries whenever I have a lesson with him.
この場合、次のような言い方ができますよ。
ーThat teacher is always moving around to different cities and countries whenever I have a lesson with him.
「その先生とレッスンをするときはいつも違う街や国にいる」
to move around to different cities and countries で「違う街や国に移動する」
ご参考まで！
アメリカ合衆国 
カナダ 
