Here is the problem. School is an aspect of life that requires discipline and more work, and kids must learn to value the value of doing well. Your kids should keep the importance of making themselves better. Motivation cannot be forced. If you try to force your kids to be motivated, it always makes things worse.
The insertion and deletion in a multidimensional array can be performed by using the indices of the cell. That is in other words a multidimensional array can be inserted or delete values by accessing the cells or the memory blocks present in it.
Multidimensional arrays are arrays with more than one dimension, that is columns. One dimensional array will have only one row and many columns but the multidimensional arrays will have more than one row and more than one column.