There are very limited options for anyone under 12 years old to make money by working in a non-agricultural business. A young person looking to earn money who is under 12 should look into either selling products like lemonade, baked goods or candy. Performing a service, like babysitting and mowing laws, is also great.
Simple low skill level services and goods are typically the only way an underage person can earn money. Despite some states allowing minors to work in agricultural types of employment, this is somewhat of a rare thing for employment regulations. In some places, a permit is required to sell goods or provide a service; therefore, a young person may want to look into individual state laws on child employment before establishing any type of business.
Working for an individual person, such as with babysitting or lawn care, is a good way to avoid having to obtain a permit, as the working contract is between individuals and would not require a permit. The best way to find a paying job for someone under the age of 14 is to research how different state laws affect the desire to work and achieve the goal of a steady income.