Super Mario Bros.: Mushrooms are good for you! The can make you grow! Similarly, flowers can give you fire powers!
Crash Bandicoot: Break all crates you can find for goodies!
Final Fantasy 8: Be a vampire! 'Draw' essences of your opponet to unlock wonderful new skills!
Kingdom Hearts: Never give into the power of darkness! Otherwise say goodbye to your world. Also, the only way to defeat shadowy creatures is by using a giant key like a sword.
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And now it's your turn. If video games actually are of educational value, what awesome things they can teach to the young malleable minds?