Always work on creating books in the library. You will need a lot of them to upgrade your students. The easiest way to them is to upgrade the library and always order the 23 hour book pack, but it is very expensive.
Coins
Keep parties running. If you do not need a specific student to join you, send random students for a party then sell the student that you get. Repeat the process as many times as desired. Maximize your coin revenue through hangouts. Fill your hangouts with students so they make money as fast as possible. Because you can sell them, whenever you get a special student sell one you do not need and they will keep making money. The higher the level of your students, the faster they will produce money. However, but the amount cannot exceed the maximum level of the hangout. This is why it is best to have more Nerd and Jock Hangouts to maximize revenue. Send your students on dates and develop their relationships.
Dates
Send your students on dates to develop serious relationships. As soon as the status of the couple changes from flirting to dating, you will start getting coins and rings.
Hangouts
There are three different types of hangouts that your students can call home.
Nerd Hangouts: Gives a maximum of 3,500 coins per hour, holds 2 students.
Jock Hangouts: Gives a maximum of 2,000 coins per hour, holds 3 students.
Prep Hangouts: Gives a maximum of 1,000 coins per hour, holds 3 students.
Keep the Prep Hangouts to a minimum. A good combination is to have one Prep Hangout, three Nerd Hangouts and three Jock Hangouts to maximize coin production.
Land
New plots of land will be progressively more expensive and require more time to become available. Some quests will require you to buy a new plot of land. When you purchase a plot of land, only unlock when you get a mission that requires it to save time and money.
Party student combinations
Throw a party and combine the indicated students to create the corresponding new type of student.
Actor: Artist + Prep
Artist (Female): Artist + Artist
Artist: Artist + any special student
Cheerleader: Prep + Jock
Dancer: Artist + Jock
Filmmaker: Artist + Nerd
Gamer: Jock + Nerd
Homecoming King or Queen: Filmmaker + Cheerleader
Jock: Jock + Jock
Nerd: Nerd + Nerd
Prep: Prep + Prep
Student Gov: Prep + Nerd
Rings
Connect to Facebook and start linking students with your Facebook friends. You can sell those classmates and get new ones using the same method. Complete missions to get free rings. Only spend rings when really needed, and to send students on dates.
Upgrades
Do not upgrade all your students over level 3. Sometimes you will need a high level student of a specific type to complete a mission; do not spend all your books and not be able to do this. Also you may need to sell students to make room for the new ones (such as gamers, homecoming students)