If you name your children as the beneficiaries to your life insurance policy, they would receive the money from your life insurance if you were to die.
However, if they are under age, then a guardian would handle the management of the money for your children, until they reach adulthood.
You may want to discuss this matter with your estate attorney or financial advisor so that the paperwork is all set up to make sure who the adult would be that would manage your childrens' money if you die.
Or, you could name your spouse as the beneficiary and he/she could manage the money to provide for you children.