As you may already have discovered this is often the hardest step in the research paper writing process. It is also a very important step. If you choose a topic that is very broad - "Poverty" - you will be overwhelmed with information and you will have difficulty organizing your ideas and findings into a manageable, cohesive paper. If you choose a topic that is very narrow - "Gifted Children Living in Poverty Benefit From Having Pet Fish" - obviously, you will have trouble finding enough sources to support your paper. Take time to focus your topic.
If you can, try to choose a topic that truly interests you. If you need some ideas, check out our libguide on Research Paper Topics. You can also view this list from Midway University: Top 100 Research Paper Topics.
Check out this short video on developing a research paper topic.
Here are some guidelines for working on your assignment.