I'm 100% sure of these chords, my mom used to play it for competitions in school and
is how she taught it to us

   G (320003@1)                      A (x02220@1)    Those school girl days
                C (x32010@1)                        G (320003@1)    of telling tales and biting nails are gone
   G (320003@1)              A (x02220@1)    But in my mind
                 C (x32010@1)                       G (320003@1)    I know they will, will still live on and on

     F#m (244222@1)               Bm (x24432@1)        But how do you thank someone
                 F#m (244222@1)                      Bm (x24432@1)        who has taken you from crayons to perfume
       A (x02220@1)        D (xx0232@1)           A (x02220@1)    E (022100@1)        It isn't easy but I'll try....

            A (x02220@1)    If you wanted the sky
         C (x32010@1)                     A (x02220@1)    I'd write across the sky in letters
                C (x32010@1)                  A (x02220@1)    that would soar a thousand feet high
        D (xx0232@1)       E (022100@1)    (riff)
     To Sir, With Love


     G (320003@1)                   A (x02220@1)       The time has come
                 C (x32010@1)                           G (320003@1)    for closing books and long last looks must end
     G (320003@1)             A (x02220@1)    And as I leave
                 C (x32010@1)                   G (320003@1)    I know that I am leaving my best friend

     F#m (244222@1)                      Bm (x24432@1)       A friend who taught me right from wrong
            F#m (244222@1)                            Bm (x24432@1)       and weak from strong, that's a lot to learn
        A (x02220@1)              D (xx0232@1)           A (x02220@1)     E (022100@1)       What! what can I give you in return

            A (x02220@1)    If you wanted the moon
     C (x32010@1)                             A (x02220@1)    I would try to make a start But I
           C (x32010@1)                       A (x02220@1)    would rather you let me give my heart
        D (xx0232@1)       E (022100@1)    (riff)
     To Sir, With Love

     G (320003@1)                      A (x02220@1)       Those awkward years
                    C (x32010@1)                   G (320003@1)       have hurried by why did they fly away
     G (320003@1)               A (x02220@1)       Why is it Sir
                      C (x32010@1)                  G (320003@1)       children grow up to be people some day

     F#m (244222@1)                        Bm (x24432@1)       What takes the place of climbing trees
             F#m (244222@1)                       Bm (x24432@1)       and dirty knees in the world outside
     A (x02220@1)              D (xx0232@1)           A (x02220@1)   E (022100@1)       What is there for you I can buy

            A (x02220@1)    If you wanted the world
            C (x32010@1)                      A (x02220@1)    I'd surround it with a wall I'd scrawl
           C (x32010@1)                         A (x02220@1)    These words with letters ten feet tall
        D (xx0232@1)       E (022100@1)    (riff)
     To Sir, With Love