1. The document discusses principles of materials development in language teaching according to Brian Tomlinson and other researchers. Tomlinson argues that materials should expose learners to comprehensible language input and engage them cognitively and affectively.
2. Researchers also emphasize evaluating materials based on how learners use them and what is learned rather than just apparent appeal. No theory can provide definitive answers and learners differ in styles and attitudes.
3. New directions in materials development include increasing technology-delivered materials and paying more attention to what teachers and learners believe and want from materials.