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    Finished · figuring out launch

    Stock Trading Journal

    A kid buys and sells on real prices, and writes down 'why I bought it' every single time.

    A project built directly by Ted TH Lee.

    Why I built it

    Stocks in the news, numbers going up and down — it's all distant to a child. I wanted them to feel the rhythm of buying, selling, and waiting without risking real money, and above all to build the habit of writing down 'why did I buy this?'

    What it does

    • Each kid trades through their own account, linked to real Korean market prices (KOSPI/KOSDAQ).
    • Every order requires a reason for buying or selling — that's the heart of the trading journal.
    • See daily profit and loss and current holdings at a glance.
    • Real commissions and taxes are factored in to keep it close to the real thing.
    • Stock detail views (candles, moving averages) to read the trend.

    Who it's for

    Families who want kids to safely build the habit of investing and reflecting on 'why I decided that'

    How it was built

    This is a practice ground for more than watching a price rise or fall. A child trades against real Korean market prices without putting real money at risk, then leaves a decision in their own words. That preserves the experience of buying, selling, and waiting while keeping it safe.

    Charts and profit-and-loss views are there to inspect the result of a decision. The centre of the app is the small field that requires a reason before an order can go through, so that reason and its outcome can be revisited later.

    How you use it

    1. Inspect a stock and its price

      Each child uses a personal account to view live KOSPI/KOSDAQ prices and stock details with candles and moving averages.

    2. Write a reason before ordering

      A buy or sell requires a written reason first, rather than allowing a decision to disappear into a button press.

    3. Return to the result

      Holdings and daily profit and loss can be read alongside the original decision, with commissions and taxes reflected in the result.

    Questions

    Does it trade with real money?
    No. It uses real Korean market prices, but it is a practice ground designed so a child does not lose real money.
    Does it provide investment advice?
    No. This is a family learning journal with no real-money trading. It does not recommend a specific stock or promise a return.
    Why require a reason for every order?
    The central habit is not only seeing a result, but recording why a decision was made and being able to revisit it later.
    Are commissions and taxes included?
    Yes. They are reflected so repeated trading also carries the feeling of real-world costs.

    Where it is now

    The first set of features is finished and verified end to end locally — it's right before deployment. I'm sorting out the scope and method for opening it up.