A key part of the planned march toward socialism is, of course, endless propaganda.

It’s not enough just to rely on the politics of envy. We need to take away those dangerous little opportunities where young people might accidentally experience the benefit of the free market in their own fledgling lives. So, how can we teach children to participant in class warfare, punish the productive by taking their stuff, and that property rights and free exchange don’t exist?

Enter Colorado’s oversubscribed, already-broke (as all redistribution schemes become) “free” school lunch program. Who could have ever guessed a $50 million take-from-thy-neighbor scheme would quickly cost $150 million?

The free lunch program taxes Coloradans who make “too much money” to purchase a one-size-fits-no-one, state-delivered school lunch. The successful are castigated so a group of elites can decide what other people’s children should consume.

Now, that’s serving up a slice of Marxism in every meal.

It’s a tiny step toward the addictive dependency state so small it’s barely perceivable. It’s right up there with outlawing plastic straws and stealing gasoline taxes to feed transit. It is the very definition of creeping socialism.

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Now, school kids might not understand someone else’s more successful parents paid for their free lunch. They’ll still think there is such thing as a free lunch. But they will be trained in the joys of equal outcome. All their peers are also eating basically the same soggy, bland meal.

As Winston Churchill observed, “The main vice of capitalism is the uneven distribution of prosperity. The main vice of socialism is the even distribution of misery.” Is there any better example of that than the wilted lettuce and greasy pizza of a public-school lunchroom?

The young get indoctrinated to governmental rations. Some committee of bureaucratic busy-bodies calculate what’s just the right formula for their hungry little brains. Gets them used to government-run everything. It will make waiting for months and months to get an MRI more palatable when they grow up.

By contrast, you might remember the loud Wall Street trading floor that was your childhood school’s cafeteria. Since all parents run their kitchens differently, what was found in lunch boxes were also wildly different.

Recall trading your peanut butter and jelly for your neighbor’s ham and cheese? A Hostess Twinkie could start a bidding war; three Oreo cookies might win over a slice of chocolate cake.

Since each kid values things differently, they use their powers of property rights and free trade to improve their individual positions. And everyone won. You wouldn’t make a trade you didn’t want.

There’s a college economics classroom exercise I’ve seen performed by Colorado economists Paul Prentice and Penn Pfiffner. The “economic wizard” teacher magically improves all the students’ lives.

The teacher has a supply of, let’s say, four edible items — candy bars, potato chips, apples and granola bars. All the students declare how much they like each item on a scale of 1 to 10. Then, like a good government planner, the teacher passes out the items to the students as he believes is best. You look like you need an apple. I think you should have a granola bar, etc.

Then given the scoring system they each individually created, they add up a cumulative class score from each student’s satisfaction value.

Then the economic wizard says, “All right, I’m not saying anything for the next few minutes,” and shuts up completely. Without prompting the classmates start trading their items like kids used to in the school cafeteria.

After the trading is done, they rescore their satisfaction with the item that they have now, which could be the same if they chose not to trade. Again, they add it up for a new cumulative satisfaction score.

Lo and behold! Satisfaction, what economists call utility (because economists hate being understood), has collectively skyrocketed! No governmental planning, no interference, no regulation. Most everyone is much more satisfied and absolutely no one is less happy. And it didn’t cost a damn thing. Magic!

This is the economics lesson that won’t be organically taught in Colorado public schools as more and more families opt for “free” lunches.

And the lessons of free enterprise, property rights and liberty take another small loss, another incalculable cost of “free.”

Nothing’s more expensive than “free.”

Jon Caldara is president of the Independence Institute in Denver and hosts “The Devil’s Advocate with Jon Caldara” on Colorado Public Television Channel 12. His column appears Sundays in Colorado Politics.