Definitions:

Indirect Object - A noun or pronoun that indirectly receives the action of an ACTION verb.  Answers the questions, to whom or what, or for whom or what, something is done.  This noun or pronoun will be located between the ACTION verb and the Direct Object.  There will NEVER be an indirect object without a direct object.

Direct Object - A noun or pronoun that directly receives the action of the ACTION verb.  Answers the questions, whom or what, after the ACTION verb.
 

Examples:
Joe bestowed an Olympic medal on the winner.
Bestowed what?  The medal.  Medal is the direct object and there is no indirect object.

The teacher wrote the students a note on their report cards.
Wrote to whom?  The students, so students is the indirect object.  Wrote what?  A note; so note is the direct object.  (NOTE how the indirect object, if there is one, is located between the action verb and the direct object.)

1. I owe you a dollar.
2. The students read Ivanhoe in their literature class.
3. Tell us the news now.
4. Will you give Marilyn the candy? (Hint: change it to a statement)
5. Mrs. Jones gave the students a homework pass.
6. The principal excused the boys early last Wednesday.
7. Who taught you about the Civil War?
8. Mr. Smith gave us a long assignment in science.
9. Have you read many books this summer?
10. Mr. Goldman gave his son the keys to his car.
11. The team is going to the tournament.  (Be careful!)
12. I like snow.
13. The helicopter is a versatile aircraft.
14. It can fly up and down.
15. Traffic controllers in the towers at the airport control air traffic.