Half of the class consists of 28 students / 2 = <<28/2=14>>14 students.
One half of the students have 14 students * 3 notebooks/student = <<14*3=42>>42 notebooks.
The other half have 14 students * 5 notebooks/student = <<14*5=70>>70 notebooks.
There are 42 notebooks + 70 notebooks = <<42+70=112>>112 notebooks in total in the classroom.
#### 112