Buying $50 worth of a stock is a terrible decision. You will lose so much money on commissions. If you have a online trading account with low commissions of $9.99 then 20% of your $50 goes to commissions. That's ridiculous. You want to get your commission down to under a percent, which means buys and sells of a minimum of a thousand dollars at a time. Remember, just about the only people who actually make money in the markets over the long term are the ones who are raking in the commissions.

Also, investing in penny stocks when you're five years from retirement is another huge investing no-no. You're basically guaranteeing that your children will be supporting you. If you want a better investment with $50 a month, buy healthy food.