Explain to students that to determine the elements of a sentence, they only have to answer a few questions. Ask students to pick any sentence from any part of their textbook. Allow one student at a time to read the sentence he has picked aloud. Then, asking him questions such as "Who kicked?" to find the subject and then "What or whom did he kick?" to help him determine the direct object.
Ask two students at a time to close their eyes, while you form two columns on the board, containing the same 10 sentences. When you are finished, ask students to open their eyes and underline the direct objects in the sentences of their respective column. The first student to underline the most correct objects wins the round. Repeat the process, so that all students get at least one chance of proving their direct object-finding skills.
Another method of determining the direct object is to rephrase the whole sentence in the passive voice. In this case, the direct object becomes the subject and students can identify it more easily. Write a series of sentences on the board, such as "Dad repaired the bicycle" and "Carol won the match". Ask students to rephrase these sentences in the passive voice, such as "The bicycle was repaired by dad," and give you the subject/direct object. To make the activity trickier, include active voice sentences that don't feature a direct object, such as "John was happy with his victory."
Divide the class into two large groups. Distribute a list of sentences with clauses as direct objects, such as "Patrick made Lucy cry," to Group A. Distribute the same list of sentences, but without mentioning their direct objects, to Group B. For example, write "Patrick made..." Ask students of Group B to take turns asking members of Group A what is it that Patrick made for instance. Students can tell by themselves whether an answer is right or wrong, because if a student of Group A replies "cry" for example, then the sentence makes no sense. When students identify all direct objects, reverse the roles and distribute a list of incomplete sentences to Group A this time.