Contract change for employment

Good day!

I am an expat English teacher working for a Chinese agency employing foreign teachers and sending them to public schools of Shenzhen to teach. My contract says that my agency is supposed to place me to a middle school in Shenzhen. But for some reason they have been trying to push me to accept a job in a primary school which is against my contract and against my will. Teaching young kids is not my thing at all and I have been pointing it out to my employer long before I was hired by them. Can this be considered as a contract breach and be enough grounds for termination of the contract due to the employer's failure to fulfill the Contract obligations and making the employer pay the 2-month salary penalty as stipulated in the contract?

Thank you in advance!