Yea they haven't told us yet but in the Last Episode "Graduation" On where Francis drops his Name tag from his Work It clearly says "Francis Nolastname" But its not their Last name tho and then later on The teacher calls up Malcolm whom is Valedictorian, but When they try to say his last name but there a was sqeak on the microphone so we r going back to the middle episodes where this kid runs to him and asks him "Hey Malcolm, What is you Last name" then Malcolm Replies"Wilkerson.Why?" and then I forgot what the other guys said so it's Malcolm Wilkerson, Reese Wilkerson, Dewey Wilkerson and at last but not least Francis Nolastname lol jk
Um, I don't know if Reese put a fake last name, or not.
But in the episode: "Reese Joins The Army", LATER ON in the episode.
MAYBE IT'S THE SECOND PART!!! ("Reese Joins The Army Pt. 2")
Lois' Mom tries to get him back.
& then like they said his name was like "Private Jetson"?
Last name might be "Jetson"...?
I hope this helped.
How I know? Is...
I watched every episode, more than 3 times, each.