Preventing students from viewing future assingments

John_P490 

:: Caveat :: This solution is for Excel only.

What you are trying is only possible by using VBA macro.

Private Sub Worksheet_Change(ByVal Target As Range)
    Dim AssDate As Date
    AssDate = Range("A1").Value
    Dim Currdate As Date
    Currdate = Date


    If Currdate = CDate(AssDate) Then

        ActiveWorkbook.Sheets(1).Visible = xlSheetVeryHidden
        

    Else
        ActiveWorkbook.Sheets(1).Visible = xlSheetVisible
        
    End If
End Sub

How it works:

To invoke VB Editor to use this code,  you will need to press Alt+F11.

• Then Copy & Paste this code.
• Return to the sheet & Save the WB as Macro enable *.xlsm.
• Write the date in cell A1 on which you want to un hide the assignment.

N.B.

• If and when the Current date will equals to the Assign date this code will unhide the Sheet/Sheets. 
• You may hide & unhide as many sheets.
• This is editable, and you may use formula as needed to compare, Current Date ( Currdate  )  with Assignment Date ( AssDate ).

If Currdate = CDate(AssDate)  Then