To check the value of a solution we do this:
Is the solution feasible? If not then the solution is useless.
If it is feasible:
Count the number of occurences of a student having just one class on a day (e.g. count 2 if a student has two days with only one class).
Count the number of occurrences of a student having more than two classes consecutively (3 consecutively scores 1, 4 consecutively scores 2, 5 consecutively scores 3, etc). Classes at the end of the day followed by classes at the beginning of the next day do not count as consecutive.
Count the number of occurrences of a student having a class in the last timeslot of the day.
Sum the three counts to give the solution score - smaller is better - zero is always possible with the instances in this competition.
You should always use the solution checking program provided in order to make sure that you have understood the constraints.