Always start off by teaching them about nouns. Make them understand the concept that a noun can be a person, place, thing or idea. Give your students a list of as many nouns as possible.
Now ask the students to tell you about different nouns which they remember. Once they give you at least five nouns, ask them to describe these nouns. The different descriptions are going to be adjectives. They tend to describe the nouns.
Once you have completed the exercise for adjectives, ask your students to assign a task to every noun which they have named. For instance if they have said ‘dog’ as the noun and ‘big’ as its adjective then the task assigned could be barks. So ‘big dog barks’ can be the sentence. This particular task which they have assigned to the noun is going to be the verb. Every action which the noun produces is a verb.
Now you need to ask them to describe this action. For instance, if we carry the same example forward, ask them whether the dog barked loudly or not. This way the adverb can be loudly. The whole sentence can be ‘big dog barks loudly. Any word that describes the action is an adverb.
Now in order to make them understand the meaning of pronouns, make them write another sentence which describes the first sentence. For instance, ‘the big dogs are here, they always bark loudly’. In this case ‘they’ is a pronoun, something which describes the other nouns but it is actually a different word.
Now add a relationship to the whole sentence. Ask them where the dogs have been barking, if they say the yard, then yard is a preposition. It describes a relationship with the dogs.
Explain to them how conjunction helps them join two different words. You can add big dogs ‘and’ small dogs to the sentence. In this case ‘and’ is going to be the conjunction word which will be joining the two different types of dogs.