Scam or not. Need help!!

I don't think your friend has much to worry about as a foreign passport can't get much done in China, especially if it's just a copy. To open a bank account, they'll need the originals of your passport and Visa page.
Most scams in China are monetary or cash scams. Hell I wish someone could steal me a Chinese ID, it'll make my life so much easier!

It is, to the best of my knowledge, for recruiters to ask for copy of Degree, data page of passport & cv. This helps to confirm applicant. If you have had Government letter of invite, the next step is you apply for Z visa.  There is a Web page that lists black listed company's in China. You never completed your research! I hope all goes well, as the majority do.
By the way. I am also a recruiter for Native English speaking teachers

I had many interviews and are now in China waiting for my job to start. It's absolutely normal for them to ask for these documents, so I definitely wouldn't worry.

Don't mind the scanned copies. It won't do any good to those who intend to use it on some unlawful purposes.. Those scanned copies needs to be backed up by the physical presence of the ID holder. Besides, your friend probably entered into a negotiation with a third party job agent looking to make money if they get to recommend a foreigner to work in a school. If successful, the school pays off their commission.

Thank you so much. I told her about all your comments. She is so happy to hear they can not do anything with her scanned passport. You are all great 

Although a lot of scams happen in China - you do need to show the original passport to open anything and apply for visa's, bank accounts and such like.
It is more likely the agency does not have a real contract with the provider of the job and are offering candidates in the hope of getting a commission from the school.  If you do not hear from staff it is because when they do not succeed they forget you and turn to the next person or job. Do not expect polite behaviour or good manners in your dealings here.
Good luck with your search.

Kind regards, Dr Stephen

keep on with good work of making people aware of frauds.

but why should an employer or recruitment agency ask for potential employee for bank accounts details?  People ought to be careful not to be conned their money.

It is highly unlikely they are using the documents for a bank account, but in some cases the information may be used in advertising or promotional materials for prospective students at small schools like private kindergartens. The parents get tricked into signing their kids up and somebody else who may not speak English as a first or even second language ends up teaching the class. The best way to identify if a job opportunity is a scam is by the type of visa you will be provided with. If the company can provide you with a legit work visa (Under normal circumstance the original one is single entry and only lasts 30 days. You have to get it renewed once you're in the country.) then you know at least the company that will be hiring you is legit. What the position turns out to be is a whole separate issue.

You didn't real the post well. They never asked for bank account details.
She's worried her scanned pspt will be used to open a bankaccount!