Only one machine is needed. It's easy to keep a class together. More material can be covered. Disadvantages - Projection equipment will be needed and visibility may be a problem. Students may not be as interested.
Individual students take turns working on a single computer.
Advantages - Creates access for the classroom with only one computer. Works great if material is self-explanatory. Disadvantages - It takes a long time for each student to get a turn. Some students will require individual tutoring. A student will miss the regular class activity while doing the individual project.