Use them individually, grouped by subject, or mix and match. Some do represent building blocks for competitions, but no activity is a direct pre-requisite for another. Depending on your available computers and teaching preferences you can have students work as individuals or in groups. We recommend working in groups of 2-4 students per workstation. This generates excellent discussion and shared learning.
Several tools are available.
First, many activities come with grading templates. Second, you can use the online CyberConsultant to assign grades. We even provide a graphing tool so you can see how each decision affected sales, cash flow etc. The School Edition of Virtual Business is the classroom product. It has unique features that are not available in the Home Edition.