Honestly the best Idea is to ignore 90% of what they teach you...

Honestly the best Idea is to ignore 90% of what they teach you in economics class( If it worked in the real world then economists would be rich, and wouldn't be writing text books).

Be very careful about the advice you seek from this forum- everyone is very bias to the stocks they hold. The trouble is most of the talk around here is based around penny stocks, where the odds of success are stacked against them.

If you want to learn how to "invest" then perhaps start by reading some of the work my Benjamin graham, or model someone else who is successful( Read the Market Wizard books by Jack D Swagger, and Reminiscence of stock operator by Jesse Livermore).

You also have to consider that in the near future "investing" in stocks using buy and hold strategies might to be the most efficient way to make money in the stock market. So you need diversify your understanding of the market- learn some trading methodology's/ trading systems, and gain a better under standing over basic things like price structure, and how to manage individual positions with risk/ reward(money management).

No one else on HC will tell you this, however the most useful thing could actually be learning how to code, and learning how to back test strategies through the likes of quantitative analysis.

Quantitative investing is what young people should be seriously looking at, it's quickly going to evolve into the retail sector.