This is a very common use of "把“，the structure is (S)+把+N+V+在/到+place Word，to show the noun after the action of verb, has move or shif. For example:
1. 妈妈把午饭送到了我的学校。ma ma ba wu fan song dao le wo de xue xiao. Mother sent the lunch to my school.
2.请把书放在桌子上。qing ba shu fang zai zhuo zi shang. Pls put the book on the table.
And your sentence, 我把（我的）钱包落在房间（里）了。
first,lunch is not at school,after mother's transfering, it has move, in school now; the book after the verb put, has move, on the table now; the wallet is not in the room, but because you forgot to bing out, it is in the room.
So you can produce lots of sentences following this sturcture. Hope this can help you.