I teach English to teenagers and preschoolers. For teenagers, I don't need many material resources.

For the preschoolers, I borrow books from the library for the reading time at school. While teaching them colors, I do not have those color cards so I let the students go outside and observe the environment to learn colors. For example, sky as blue, leaves as green, wood as brown, flower with different colors. In this way, they become more interested and make them easier to remember. But it put an extra work for me to watch them carefully while going out.