Two students are thought to have been involved in the baking of the biscuits, which were sampled by at least nine youngsters
at the Da Vinci Charter Academy just west of Sacramento.
Nobody has suffered any ill effects, and cremated human remains are not poisonous, although Davis Police lieutenant Paul Doroshov told The Sacramento Bee "there could be some emotional issues experienced".
The officer added that the motives behind the culinary crime were unknown, but said the suspects were unlikely to be charged and that officers would leave it to the school to handle the issue.
He admitted he was unaware as to whether baking human remains into food could be considered an actual crime, noting that it would "probably take some legal debate to figure out".
In a letter sent to parents, headteacher Tyler Millsap said the pair were remorseful and that it had become a "personal family matter".
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And in a further statement, he assured locals that there was no health risk to the wider community.
He told the Bee: "We always take allegations of wrongdoing seriously and we conduct thorough investigations and involve the police or other entities when appropriate."