There were many differences between Athens and Sparta from their values to their slaves. In Athens, they trained their mind, body, and spirit. But, in Sparta they would only train the body to prepare for war. Their values differed immensely and that's not even half of the differences.
Athens and Sparta both made their money in separate ways. Athens' economy was based on trade and agriculture. Sparta's economy was based on military and conquest! Still don't think they're different, I do.
Governments in Ancient Greece also differed immensely. In Sparta, they were under an oligarchy run by five ephors and a thirty man senate, these thirty-five men truly made all decisions for all of the city-state although there was a public assembly. But, in Athens, they were under a democracy which is a government where the people run the city-state. Although these two city-states both lived in Ancient Greece, they both led different lives.
They both had one way or another of education. In Sparta, boys from the age of seven to twenty would be trained for the military which would be the only type of education boys would get. On the other hand, Athens had boys of wealthy citizens go to private schools at the age of six, accompanied by a tutor or pedagogue. These two city-states have different ways of giving education but that was the way they were set up at the time.
The role of women varied immensely in Athens and Sparta. In Athens, they didn't get formal education; they had to be taught by their mother. They also were taught to run the house but they never participated in sports. In Sparta, they lived a much freer lifestyle then elsewhere because they were allowed to participate in sports and own business and property. So, do you know which one you want to live in yet?
Finally, the roles of slaves were extremely different among these two city-states. In Athens, slaves were treated decently but they were people taken during war and forced into slavery. In Sparta, they called their slaves helots and they were treated cruelly, but they were also people taken during war and forced into slavery. All in all, Athens and Sparta may have both been in Ancient Greece, but they were way different from each other.