Explain the theory thoroughly one time. Abstract thinkers should be able to grasp the theory if you explain it carefully and show how everything fits together. Explain the general principles of your material and how they function. Abstract thinking applies to almost any discipline, including math, philosophy and English grammar. A standard mathematical or scientific formula is an example of abstract thinking.
Give plenty of examples and relate all ideas to real-world objects. Concrete thinkers will need these specifics to grasp the material. When you're preparing a class, choose material that relates to everyday life. For example, with a math class, rather than teaching raw numbers, use numbered objects like apples or apply more complicated math to situations like calculating the velocity of a car.
Show how you can derive general principles from specific examples. Although it may be easy for concrete thinkers to see how to apply general theories to the real world, the opposite may not always be true. Show how the repetition of concrete examples can lead to abstract principles. This is often how children learn. If a hurled rock, brick and ball all break a windowpane, it stands to reason that throwing any heavy object will break glass.
Provide visual aids that illustrate the theory you're teaching. Your whole class will benefit from seeing the relationship between the abstract and the concrete. Rather than explaining the hydrological cycle, show pictures of how the water falls as rain and rises with evaporation.
Elicit examples. Whenever teaching abstract theories, ask for several concrete examples of that idea. This will force your students to pay attention and actively link abstract to concrete thinking. If you're teaching grammar, ask for examples of various parts of speech, such as nouns, verbs and adjectives.