Function Analysis System Technique (FAST) diagraming is a key component of Function Analysis. It contributes to Value Engineering (VE) teams’ understanding of the scope of VE studies and maximizes the number of identified VE alternatives. This paper identified some of the challenges encountered by university students in constructing FAST diagrams. This was accomplished through the assessment of 36 FAST diagrams constructed by 36 students and five FAST diagrams constructed by five teams of 24 students. The assessment found less flaws in FAST diagrams when students work as a team rather than as individuals. The analysis also found difficulties associated with understanding and linking functions in the When logic or same time functions. To overcome this issue, the paper is suggesting the use of a “Function Block” approach to facilitate the understanding and construction of FAST diagrams. The new approach was tested by three teams of 13 students to identify its advantages and disadvantages.