Pandas: How to turn table of grades by student and subject to a pivot table indexed by student and subject

Question

Let's say I have a dataframe with student grades by subject:

  id english    cs   math  
  1       63    71    55  
  2       87    78    59  
  3       50    77    91  
  4       89    93    87  
  5       55    82    96 

Is there a way to get the following pivot table:

1 english 63
1 cs      71
1 math    55
...
5 english 55
5 cs      82
5 math    96