Investing in the stock market is key to earning investment returns that allow your money to grow at a reasonable pace.  Unfortunately, many Americans find it difficult to save enough to get started investing. Some mutual funds, for example, cost thousands to invest in. Even buying and selling ETFs or individual stocks can be expensive for small investors, with discount brokerage firms charging anywhere from $14 to $20 in fees to buy and sell.  Brokerage firms where your money is managed for you typically also have high minimum investing requirements, making it a challenge for beginning investors to find a place to stash their cash. 

The good news is, there are options if you want to get started investing in stocks and you've saved up only a small amount of cash to do it. If you have $100 or less you want to invest in the market, here are a few places where you can put your money to get your cash working for you. 

Stock market chart

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Ready to put your trust in the robots? 

Betterment is a Robo-Advisor, which means a computer algorithm is used to manage investments.  Since there is no human financial advisor to pay, it's far cheaper to manage money and cost savings are passed on to those who invest. Betterment is just one of several top-rated Robo-Advisors, but it's a good one for those who are just jumping into the market because it has a $0 minimum balance requirement. You can start investing with whatever cash you have saved and add to your account over time. 

Betterment's digital plan, ideal for beginning investors, charges a fee of .25% annually. For this fee, you'll get automated investment management, free trades, fractional shares, automatic rebalancing, and tax-efficient investing features like tax loss harvesting and a tax-coordinated portfolio which invests more highly taxed assets in tax-advantaged accounts like IRAs. 

Betterment takes care of account diversification and rebalancing for you, which makes investing more hands-off.  Betterment also offers an array of options, including exchange-traded funds for socially responsible investors. 

Is it ETFs all the way for you? 

Stash is an alternative to a Robo-Advisor that empowers you to build a portfolio of Exchange Traded Funds yourself. Instead of a Robo-Advisor managing money for you, Stash guides you through the selection of funds that are good investments for you. Stash has an account minimum of just $5, although you will pay a $1 monthly fee if your account balance is under $5,000 and a .25% fee once your account grows to $5,000 or more.  However, you do not pay a commission on trades when you invest with Stash and you don't pay a fee for inactivity or funds transfers.

Stash makes it easy to choose appropriate investments by asking you a few questions when you open up your account. The app suggests ETFs based on your risk tolerance and investing goals. You'll receive a list of proposed ETFs that briefly explains what each fund does and who it is appropriate for -- for example, a fund may be listed as an aggressive mix or a hedge against inflation.  The app also suggests where you should invest the largest portion of your money and you'll be offered suggestions and educational information if the investments you chose don't result in a diversified portfolio.

Do you want a little more control? 

If you're comfortable taking more control of your money and want a low-cost investment account with minimal fees for trades, Ally Invest may be a great option. Ally invest allows you to begin investing with no minimum balance and you can make trades for just $4.95 per online stock and ETF trade -- which is lower than most discount brokers. 

There are downsides to Ally invest, including the fact the company has no commission-free ETFs and no mutual funds free of transaction fees. However, you have a wide selection of investments, a robust trading platform, access to comprehensive free research, and lots of tools to analyze different investments. And if you want to trade stocks with $100 or less -- rather than make fund investments -- Ally investments is a low cost way to do it. 

Just get your cash in the game

All of these options give you the chance to get your cash in the game, even if you don't have a ton of it. Whichever option you chose, don't leave your cash on the sidelines any longer. Pick a plan today, get that money out of a checking or savings account where inflation is eating away at it, and put your cash to work.