Just as people have inherent likes and dislikes, preferring one thing over the other, and thus, finding it better, students often have an innate understanding of comparatives and superlatives. Thus teaching these concepts in any classroom is a straight forward task; the teacher usually just needs to fine tune her students' understanding. Comparative adjectives do exactly what their name alludes to: they compare two nouns. A superlative adjective compares three or more things and sets a notion of extreme quality. Luckily, it's easy to clearly demonstrate these concepts to groups of students.
Show the class two apples, or any other objects you'd like to compare. For example, show one small, pale red apple and show a large, shiny red apple.
Elicit comparatives from the class by asking students leading questions. For example, ask students "Which apple is small?" or "Which apple is shiny?" to make students aware of the differences between the apples.
Put the structure for making comparatives on the board: adjective + -er. Write an example on the board using one of the apples. For example, hold up the small apple and write, "This apple is smaller." Elicit more sentences from students about the two apples, such as "This apple is redder than that one."
Show students the shiny apple and elicit from them the same comparative, "This apple is shinier." Be sure to highlight for students how the Y changes to an I in comparatives.
Write down irregular forms of comparatives, so students have them to refer to. For example, show how the comparative adjective of "good" is "better," "little" is "less", "bad" is "worse" and so on.
Give students worksheets, which focus on this aspect of comparatives, and ask students to complete them on their own. Check their understanding by going over the worksheets or examples as a class. This is referred to as controlled practice, and it allows you to determine if students have understood the basic concepts presented and can use these forms on their own.
Introduce a third apple to the class. This apple should be a very deep shade of red, very big and very shiny. Write the form for superlatives on the board: the adjective + -est. Ask students "Which apple is very, very big?" All students should point to the third apple. Write on the board in a full sentence, "This apple is the biggest."
Elicit other sentences from the students about this apple, such as "This apple is the reddest" or "This apple is the shiniest." Point out to students what happens to adjectives that end in Y in the superlative form. Just like comparative adjectives, the Y is changed to an I before adding the ending.
Write the form for irregular adjectives that have an irregular superlative form. Show that the superlative adjective for "bad" is "worst," "good" is "best," "little" is "least" and so on.
Hand out worksheets, which directly address the use of superlatives. Ask students to complete them individually and then go over them as a class. These worksheets are the controlled practice of your lesson plan and will directly assess how well your students understand the superlative form.
Put students into groups and give each stacks of magazines. Ask them to cut out pictures of people and compare them using superlatives and comparatives, presenting their findings to the class.