Photos from the flee market

I just bought these on flee market for 7 euros. Can anybody tell me anything significant for these photos.
On the group photos there is writen: P.Johanns, Photograph, Rue Elisabeth, Nr. 7, Lux-Gare.
This photo looks to me like school photo, in front of church school or something.
There is hand-writting on the back. I cant understand it. I can see 1904.

The other photo is portrait, on thin cardboard. There is no writings, signs, years.

I would like to know anything about these photos, like who are these people, where are they taken, where is the location of the church etc.. anything