Unicorn Way (of course), Triton Avenue, Firecat Alley and Cyclops Lane. Colossus Boulevard is only for if you want to be more of a higher level when you reach Krokotopia. And each time you finish a street, you get sent to talk with the Headmaster. (Ambrose.) Then the Headmaster would just give you about 200+ Experience. If you completed all the streets (story line quests), It would get different. He gives you a quest to locate Sapphyra's Tower (Foulgaze) and then defeat the boss inside. (Foulgaze.) He is currently 510 Health and with a Minion which is a Haunted Guard. (395) Depends how many people go in with you. (You'll find out.)
Then after you defeat him, you talk back with the Headmaster and he tells you to locate Stormdrain Tower and defeat Lord Nightshade (690) and a Field Guard. (395) Then after you defeat him, you will find a book and a skeleton key. You give that to Ambrose and then he tells you to explore Nightside behind the Waterfall. Then after you enter Nightside, you go explore the Death School and then talk to Dworgyn and then talk back to Ambrose. Then he gives you a Spiral Key to Krokotopia and get your 2nd Potion. Huzzah and hope I helped!
obviously you did not beat all the missions wizard city has to offer. there are manny other missions beside unicorn way.it says underneath your post that you are anovice i guess you have to work on that.