I'm not sure if we write "r" the same way you do, but, unfortunatelly, I'm not very familiar with handwriting in English
here I found some text written by a teenage girl,
Aha, interesting sample, thanks! Sort of half-longhand, half-print. But it confirms what HAL9009 was saying about the Polish ł being written like English i, except with a flat line over it, and about lower-case Z being written like a small upper-case Z. Neat! :)
So at least half the puzzle is solved, I think. The Polish "r" looks the same as ours, although one person's style will differ a bit from the next, and the picture was a bit blurry I think, although that might just be my computer's settings.
If anyone can post additional examples, that would be very welcome, but for now at least it makes some sense to me. :)