As /u/mormengil said, your question is far too broad for us to answer. Historians have written literally thousands of lengthy books about the Constitution of 1788. You could pick myriads of subtopics to write a paper on - how contemporary historians viewed the Constitution in some decade, how modern historians view the Constitution's workings in some period of time or in some event, how historians view some individual clause of the Constitution, or many, many other things.

If you're looking for an overview of the topic, or of some subfield (e.g. "the Constitution during the Civil War," which I've read multiple full-length books on), your university library would probably be a good place to start. The librarians are trained to answer questions like this. Afterwards, if you want to ask more specific questions about your paper after you choose a thesis or topic, feel free.

Here's a post from a couple weeks ago about how to phrase questions about paper topics well. For instance, "How was the Constitution viewed in the Civil War?" is probably too vague. "How did Lincoln view the Constitution in relation to the creation of West Virginia?" is a good, targeted question (and one that's sparked at least one good law review paper, and a lengthy chapter in a book). An even better question might be "I've read these articles about the Constitution and the creation of West Virginia, but I'm still not sure how the Second Wheeling Convention itself viewed the Constitutional restrictions on forming new states. Can someone point me in the right direction?"

Your question is somewhat confusing.

There was no "US Constitution of 1878".

The only Constitution produced in the US in 1878 was a constitution for the proposed State of Washington. This was voted on and accepted by the inhabitants of Washington, but the US Congress did not grant Washington Statehood. By the time Washington was admitted to the Union in 1889, a new constitution (that of 1889) had been adopted and the Constitution of 1878 never applied.

If you are referring to the Articles of Confederation, which preceeded the US Constitution. These were adopted by the Continental Congress in 1777, but not ratified by the States until 1781.

If you are referring to the US Constitution, this was ratified in 1788 and came into effect in 1789.

To what "US Constitution of 1878" are you referring in your question?