The girls from a school in Berlin described their encounters on Deutschlandfunk radio.
Four of the girls who were wearing the hijab say they were abused.
One girl said a man had spat on her in the street in Lublin whilst the police stood their idly grinning.
Another girl said she was kicked out of a shop for speaking Persian on the phone to her brother.
She told the radio station: “They came up to me and said ‘can you leave, you’re disturbing the people here’. And I thought: Why? Just because I’m speaking Persian and I’m a foreigner? Yes.”
A Lublin police statement issued yesterday said “the trip participants did not report any complaints to Lublin police officers”.
The schoolgirls approached two policemen in English, who “heard from the people translating that there was no problem”.
The statement added: “The people exchanged polite smiles”.
It also said local police had examined CCTV footage, but it did “not show any incident involving foreigners”.
The Muslim schoolgirls said that a market stallholder in Lublin refused to sell them water because they were foreigners.
In another incident, one girl was allegedly threatened with a knife.
One girl described that in Lodz “a woman just came up to me and shouted ‘get out!’ and threw her drink over me and my camera – she said ‘get lost!'”
The girls were among a group of 20 children – mainly Muslims – from the Theodor Heuss Community School in Berlin.
Poland’s right-wing government has refused to take in Muslim refugees from Syria, stating that they would “struggle to integrate” in the country’s Catholic-majority society.
Defending Poland’s policy, Science and Higher Education Minister Jaroslaw Gowin said “every nation and people has a right to protect itself from extinction”.