If my old history Teacher was correct where Vermont and New Hampshire are that part used to be Massachusetts, Why did this happen and why didn't they just form one big colony? Why did they split?
Vermont was part of New York; it declared independence from the state in 1777, while the Revolutionary War was going on, because NY's governor refused to acknowledge some land claims there.
https://en.wikipedia.org/wiki/Vermont_Republic
No idea how Massachusetts ended up with two non-connected sections, but Maine was made a separate state in 1820 as part of the Missouri Compromise, balancing the number of free and slave states. There was a lot of resistance to Missouri entering the Union as a slave state, so the compromise was twofold: one, that Maine would become a free state to maintain the balance between the two factions in Congress; and that no new slave states would be admitted north of a certain point (which is why Missouri, Oklahoma, Colorado, and Utah all hae the same southern border, and Missouri has that notch dropping down to cheat the rule.