It’s brought to you by the letter P — for prison.

PBS’s “Sesame Street” is moving from ABCs and counting numbers to offering its young viewers a bigger lesson in life: how to cope when Mommy or Daddy lands behind bars.

Called “Little Children, Big Challenges: Incarceration,” the program is distributing “tool kits’’ to schools, community centers and even jails in 10 states — including New York — starting today to help kids ages 3 to 8, organizers said.

According to one “tip’’ for caregivers, “Before you visit your incarcerated loved one, let your child know some of the things she can expect to happen. For instance, ‘We won’t be able to sit in the same room with Mommy, but we can see her through a window and read a story together.’ ’’

“Phone calls are a great way to reach out,’’ another offers. “Help your child to think of something she’d like to tell her incarcerated parent, and give her a photo of her parent to hold during the call.”

And one instructs: “When explaining where an incarcerated parent is, you can say, ‘Daddy is in a place called prison (or jail) for a while. Grownups sometimes go to prison when they break a rule called a law.’ ’’

A video in the kit shows two Muppets — Abby the fairy and lovable monster Rosita — dealing with a little Muppet boy who shamefully admits to them that his father isn’t around to help him build a toy car because he’s in jail.A woman with the kids then tells the boy she knows what he’s going through — because her own dad was in jail when she was his age.

According to “Sesame Street’s’’ Web site, the initiative received “major support’’ from aerospace giant BAE Systems Inc. The Prudential Foundation, Robert R. McCormick Foundation, USO, and Military Child Education Coalition also provided money, it said.

Reps for “Sesame Street’’ — which receives funding from the federal budget and private sponsors — did not return requests for comment on whether any taxpayer money is being spent on the initiative.

A woman responding to a Web article about the incarceration kit called the program “pretty awesome.’’

“My brother is in federal prison (conspiracy and gun charges . . .) and it isn’t exactly an easy situation to explain to his two sons who are 5 and almost 4,’’ the writer said.

About 105,000 children in New York state currently have at least one parent behind bars.

“We’re thrilled’’ about the program, said Tanya Krupat, program coordinator for the New York Initiative for Children of Incarcerated Parents.

“It’s a population that’s in the millions that people usually don’t focus on.”