Solution
The counselor has 12 electives courses (e.g. art, band, PE, etc.) to choose from and must select 2 ordered classes for each 6th grade student.
Let S be the sample space.
Then, n(S) = 12C2 = (12 x 11) ÷ (2 x 1 ) = 132 ÷ 2 = 66
Sixty six (66) ways can the counselor arrange the last 2 periods of the day for the 6th grade students
