Campaigners complained about the sports kits, after they were introduced ahead of a play-off game at Animas High School in the US state of New Mexico on 27th February.
In a letter to the institution's Superintendent Loren Cushman, the Freedom from Religion Foundation (FFRF) said such promotion of Christianity was unconstitutional to "endorse a religious message to students".
Legal fellow at the FFRF, Chris Line wrote: "Federal courts have ruled public school coaches and athletic personnel must not promote religion."
In a response received by the Foundation from Animas Public School said: "We will address each of the areas of concern during our staff in-service training at the start of the next school year."
"The coach has submitted his resignation from the district".
FFRF Co-President Annie Laurie Gaylor said: "We're pleased that the Animas school system took us seriously in remedying a constitutional violation.
"Such behaviour cannot be excused in public schools."
Boasting more than 31,000 members across the US, the FFRF promotes awareness in public life of non-theism - disbelief in God.
Picture: Library image
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