Disordered exercises left learner and me with lines (4-4)
I believe the answer is:
pell-mell
'disordered' is the definition.
(thesaurus)
'exercises left learner and me with lines' is the wordplay.
'exercises' becomes 'pe' (Physical Education class).
'left' becomes 'l' (common abbreviation).
'learner' becomes 'l' (as in a learner driver with L-plates on their car).
'and' says to put letters next to each other.
'with lines' becomes 'll' (two abbreviations for line. I am not sure about the 'with' bit.).
'pe'+'l'+'l'+'me'+'ll'='PELL-MELL'
(Other definitions for pell-mell that I've seen before include "Headlong, as heavy rain may fall" , "In rushed, confused manner" , "Helter-skelter" , "In a rushed way" , "In hurried disorderly manner, headlong" .)