There are numerous approaches to teaching English as a Second Language (ESL), each with its own pros and cons. Each approach has a situation where it is likely the best choice. One of an ESL teacher's jobs is to select the best approach and materials for the given situation and ensure that the students are responding to the selected materials.

Student's Age
A factor that will play a huge role in what materials you should use is the student's age. Teaching a pre-school child is very different than teaching an adult. The child's attention span is much shorter; therefore the teacher will need a greater variety of materials to keep the child interested. The material will also need to have a theme that interests kids, such as cartoon characters. Adults, on the other hand, will quickly tire of such simplicity and will want something more practical and stimulating. In short, try to match the material to the interests someone of the student's age might expect to have.

Student's English Level
Starting off watching a dramatic film in English with someone who only knows a few words is not very effective. But for advanced learners it can be a great way to work on comprehension. ESL teachers should first screen all students with a simple English test to ascertain their level. Once you know that, selecting the appropriate level of materials will be much easier. But remember, regardless of the student's English level, try to keep the materials interesting. A little textbook learning is essential, but it should be varied with more interesting activities.

Class Size
The materials will also differ depending on whether you are teaching one-on-one, a class of three or four or a class of 25. Audio and video media are great tools for larger classes, but for one-on-one lessons they may seem too impersonal. For a large class it will be hard to individualize materials. When working with one or two students, it's easier to choose materials with which they are comfortable.

Individual Learning Style
After you've been with a student for a few lessons, you should start to pick up on his strong and weak points. Some people learn best when they can see the language while others do better hearing it. Once you know which type of learner a student is, you can focus your materials to his style. For large classes where there is a variety of learning styles, you'll also need to use a variety of materials to ensure everyone receives what they need.

Specific Purpose
For students learning English for a specific purpose, such as business or medicine, you will need to use specific materials. These learners are usually either advanced or have a short period of time to learn as much essential material as possible. Watching Sponge Bob Square Pants will not serve the needs of a business professional trying to learn enough to make a good first impression. In this case, the materials should mimic real situations the person is likely to encounter.