Here's what rhymes with undisciplined.

Consider these alternatives

inexperienced / experienced uncouth / truth underachieving / leaving uncoordinated / coordinated ragtag / backpack untrained / obtained unmotivated / stated ineffectual / intellectual irresponsible / responsible unsophisticated / dated unruly / newly uninspired / desired disobedient / obedient sloppy / body amoral / moral apathetic / magnetic underpaid / made disjointed / disappointed immature / full notoriously / gloriously