For our alternative education program and our students, nine-weeks seemed to be about right. You might only use the program for a week or so. I designed the course to take the focus off of the mathematics and place it on something a little more fun and interesting - a vacation. There is still a good deal of mathematics involved, but it s somewhat hidden within the larger project. The results have been good.
Most students seem to enjoy the Virtual Vacation course much more so than a traditional math course.
The best part for many of them is that they are allowed a great amount of creativity in the project. In addition, I have allowed a great deal of lattitude in regards to the students' trip journals. Since I offer prizes to the team that finishes the trip with the least amount of money spent, some work hard to have the cheapest trip. So, they really do their homework to find the vehicle with the lowest price tag and best fuel mileage. Others don't care about the prize and try to spend as much money as they possibly can.