Every parent knows that someday they must have “The Talk” with their kids. There’s the talk about sex and there’s the talk about drugs and many financial experts also say there should be a talk about money.

We will trust that their parents delivered the sex and drugs talks, but there may be some concern about whether the parents of Gov. David Ige, Mayor Kirk Caldwell and City Council Chairman Ernie Martin ever had the money talk.

Last week, the state learned that Ige’s precedent-setting plan to air condition or at least cool 1,000 public school classrooms with $100 million in state money by the end of the year was both way too ambitious and way under- funded.

The early critics were calling the state plans to spend $100,000 per cooled classroom an overpayment, but when the Department of Education started to open the bids, it found that the over-heated building climate was hotter than the expected August temperatures.

DOE officials pointed to preliminary plans calling for spending $20,000 per classroom that morphed into actual bids of $135,000 per classroom. The result was the DOE calling off the 1,000-classrooms-in-2016 target and Ige saying he was “extremely disappointed.”

A 2015 Wall Street Journal report notes that many parents have failed in teaching their children about money, and the cause was that the kids needed more math classes.

“Students required by states to take additional math courses practiced better credit management than other students, had a greater percentage of investment income as part of their total income, reported $3,000 higher home equity and were better able to avoid both home foreclosure and credit-card delinquency,” the WSJ reported.

So was it bad math skills that caused Honolulu’s rail line to go from $3.5 billion to either $8 billion or $10 billion in a little more than a decade, and would this not have happened if Caldwell and Martin really learned their multiplication tables?

While the $10 billion figure is a projected possible estimate, the same formulas two years put the projected possible cost figure at the $7.59 billion figure now accepted as reality.

In the first story about the possible overage, Honolulu Star-Advertiser reporter Gordon Pang quoted rail board chairwoman Colleen Hanabusa as warning that “if the decision is that we need to search for additional funds, then we have got to be realistic as to how much this project is really going to cost.”

The Wall Street Journal article points out that children not taught about money “later in life feel ‘clueless,’ as if they don’t truly understand how credit cards or money management works.”

Parents, imagine how you would feel if not talking to the kids about money results in taxpayers on the hook for a rail line budget heading north of $10 billion.

Richard Borreca writes on politics on Sundays, Tuesdays and Fridays. Reach him at rborreca@staradvertiser.com.