I have only 3 fields in the query and only want to know how to display only once the students who meet the criteria in the query.
I can display the desired results with 2 fields, but when the 3 field is added multiple records occur. I tried using 2 queries with similar results. Can some plase help me with this?

If your query is taking data from one table then you have multiple entries in the table for that student.

This though sounds as if you are trying to take data from two tables wiht the third field from the second table, where you haven't linked the tables together. If that is the case then you need to click on the common field of the two tables and drag it to the second table to create a link.

If neither of these scenarios are the case, could you please give more information as to where you are gettign your data from for this query.

You don't actually need to display the column containing the selection criteria - uncheck the box to not show the field. Then change the query's UniqueValues property to yes.