Classification when variables are in ranges
Option 1

Convert range to numerical features. You can create 2 features from it.

     range
-------------
7:00 to 14:00

becomes


percentage of day in school | hours in school
----------------------------|----------------
            0.29            |      7


Option 2

Convert range to a hot-encoding. You can create 24 features from it.

     range
-------------
7:00 to 14:00

becomes


at 0:00|at 1:00|at 2:00|at 3:00|at 4:00|at 5:00|at 6:00|at 7:00|at 8:00|at 9:00|at 10:00|at 11:00|at 12:00|at 13:00|at 14:00|at 15:00|at 16:00|at 17:00|at 18:00|at 19:00|at 20:00|at 21:00|at 22:00|at 23:00
-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------
   0   |   0   |   0   |   0   |   0   |   0   |   0   |   1   |   1   |   1   |    1   |    1   |    1   |    1   |    0   |    0   |    0   |    0   |    0   |    0   |    0   |    0   |    0   |    0 


Option 3

Combine both options for a total of 26 features.