Accepting input from user

I am developing a student grades report on excel for my students. I need to accept a number from the user(the number of students in the class) and allocate so many cells for various fields such as name, age, grades. To calculate grades, I need the formula to be automatically copied to as many particular cells as there are students present.

for example, if user inputs as shown below,

Number of students = 30

then automatically 30 cells should be allocated for various fields such as

Number NAME age GRADES
1 I will write the formula only for first cell
2 these formulae should be copied automatically
3 copied automatically
4
...

29
30


How can this be done?