Think about your answer, then reveal below.
Model answer: Natural materials come from nature (plants, animals, or the earth) and are not made by people. Synthetic materials are made by people in factories using chemical processes.
The key difference is origin. Wood, stone, cotton, leather, and silk are natural. Plastic, nylon, polyester, and fiberglass are synthetic. Some materials are tricky — rubber can be natural (from rubber trees) or synthetic (made in a factory), and processed materials like paper started natural but were manufactured into a new form.