Whenever you make a deposit into the bank or have direct deposit of money going into your bank account the money deposited into your account is reported yearly to the IRS.
If you make several deposits and never report it yourself to the IRS then they have a system in place that will flag your information and then they will audit you to find out about your money.
So you can never hide money and income from the IRS so you do need to file and report your earnings because eventually the IRS will find out and then it will be much harder for you to pay your IRS income taxes.