Here's why:
* Simple Sentence: A simple sentence has one independent clause, meaning it expresses a complete thought and doesn't rely on other clauses to make sense.
* Independent Clause: The sentence has only one subject ("the students") and one verb ("wanted").
* Complete Thought: The sentence conveys a complete thought: the students had a desire to go on a field trip.
Let me know if you have any more sentences you'd like to analyze!