A Manhattan couple filed a lawsuit claiming they were duped into paying $50,000 for a finger painting created by their son’s kindergarten class.

Jon and Michelle Heinemann are suing the Cathedral School of St. John the Divine for at least $415,000, alleging that the Upper East Side private school forced them to pay $50,000 for the finger painting after a teacher drove up the price at a fund-raising charity auction, the New York Post reported.

The Heinemanns could not attend the auction, but promised the school that they would put in the winning bid for the finger painting as long as the price did not exceed $3,000.

“This is essentially a painting done by 5-year-olds,” a source familiar with the family said, referring to the $50,000 finger painting.

The Heinemanns lawsuit against the private school, filed in Manhattan Supreme Court, also alleges that the Cathedral School of St. John the Divine mistreated their son, Hudson.

“Plaintiff’s son was consistently left out of school exhibits and films . . . and was made to go last at nearly everything,” the lawsuit stated. “On one occasion, plaintiffs’ 5-year-old son was relegated to the role of ‘door-holder’ and ordered to hold the door for all of the other students.”

After the Heinemanns complained about their son’s treatment, the school’s principal and other administrators agreed to talk to Hudson’s teachers. Following that gesture of good will, the couple donated several items for the March 1 charity auction. Those items included $6,000 worth of designer clothing and the fingerprinting artwork that Hudson’s class made with the help of his mother, who is a “renowned artist,” according to the suit.

After learning that similar works of art fetch between $500 and $1,200 at school auctions, the Heinemanns agreed to bid up to $3,000 for the finger painting.

But the price of the finger painting went beyond that limit after the private school’s director of advancement had a teacher bid up the price of the artwork to “the outrageous sum of $50,000,” according to the lawsuit.

A spokesman for the family said the Heinemanns were left with no choice but to file the lawsuit.

“The Heinemanns tried to settle this matter without a lawsuit, but the cathedral had no interest in taking responsibility for their actions,” the spokesman, R. Couri Hay, told the Post.

The lawsuit seeks compensation for the costs of having Hudson attend another private school, which costs $20,000 a year, according to the paper (tuition at the Cathedral School runs $39,000 a year.) The litigation also demands $60,000 for the salary of Hudson’s chauffeur.