Video games are tending to include an in-game investment system. Players can spend on items which confer an immediate benefit, but they can also invest for the long term by spending on items with a delayed or gradual payoff.
I'll illustrate with a few favourites, all of which are free to play.
In Plants vs Zombies (app for mobile) these investment vehicles are sunflowers. They produce sunshine, which is the in game currency, so the more sunflowers you plant, and the earlier you do so, the more you'll have to spend on front line plants which directly attack the incoming waves of zombies.
You won't last long without at least a few sunflowers, but as they cost sunshine to plant, and take up valuable real estate, its easy to overinvest in sunflowers and become overrun. You need to constantly assess how well you're fending off the zombies, and either slow or increase your rate of investment in response.
http://www.popcap.com/plants-vs-zombies-2
Bloons Tower Defence (desktop browser) is similar, if a little more subtle. While the sunflowers in PVZ pay themselves back almost immediately, the banana farms in BTD5 take more than a dozen levels before they've recouped their purchase price.
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Since popping incoming bloons (balloons) also generates income, its possible to survive the first 50 waves, on easy mode, without any banana farms; giving casual players an opportunity to spend up big without worrying about investing. When you start playing on Medium and Hard though, you'll find you're being overrun by wave 60 unless you make clever investments in the first few dozen waves.
https://ninjakiwi.com/Games/Tower-Defense/Bloons-Tower-Defense-5.html
Path of Exile (desktop download) is a little too bloodthirsty for the youngsters. It features a different type of investment option, 'Increased item quantity' and 'Increased item rarity'. The more you prioritise one or both of these two attributes, the less you can prioritise more immediate concerns, like increases to health, strength or attack speed.
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They won't directly help you survive battles, but over time they'll deliver more, better items dropped by slain monsters. The less importance you afford them, particularly early in the game, the harder the game gets over time, as you struggle more and more without the top end armour and weapons you would have otherwise found.
https://www.pathofexile.com/
None of these is particularly groundbreaking, nor is this scratching the surface of the number of games which use this mechanic; but it demonstrates a fantastic trend. My children are learning about time preference. They're not lurching blindly from one short term decision to the next, like back when Mario and Ryu wore blisters in their Dad's thumbs.
When a battle is going well, they look for opportunities to save or invest, trying to time payoffs to arrive just before the tide turns.
This is excellent preparation for making sound financial decisions as adults and I couldn't be happier about it.
Have a fantastic day