There are a number of different online computer programs and games that can help teach function notation. Students practice putting the number in the place of the variable allowing the student to come up with a solution. The students can challenge one another on some of the games while others focus on one-person play that slowly increases the complexity of the functions.
Working problems in reverse can also help students understand the process. By giving each student a series of problems such as: f(3)=2(3)+3+1 and asking the student to figure out where the “x” belongs breaks down the problem in the opposite direction. This gives the student a thorough understanding of what is happening when you are notating functions.
Set up a series of point values on the board. Each point value will associate with a function notation problem. The teams of students work to solve the notation first in order to score the points for the team. As the game progresses, the notations become more difficult. You can increase the complexity of the game as the students begin to understand how function notation works.
The class works as a team during function notation bingo. Each time the class solves a problem or answers a question correctly, a new bingo ball is pulled from the hopper. Each student has his own bingo card and is trying to be the first to get a line blacked out. For this game you should offer prizes to the winner. It can be as simple as a small treat or maybe extra recess time.