Final answer:
The sentence structure in the given sentence is compound.
Step-by-step explanation:
The sentence structure in the given sentence “The students went to the museum, the park, and the beach on their week-long field trip.” is compound. A compound sentence consists of two or more main clauses that are joined together with coordinating conjunctions such as and, but, or so. In this case, there are three main clauses “The students went to the museum,” “the park,” and “the beach on their week-long field trip.” These clauses are joined together by the coordinating conjunction “and.” Therefore, the sentence structure is compound.