In Chapter 3 of To Kill a Mockingbird when Miss Caroline requests that Burris Ewell bathe before coming to school the next day, he retorts, "You ain't sending me home...I done done my time for this year." Miss Caroline asks what he means by saying he has done his time.
Since Scout has been accused already of being insubordinate, she remains quiet, but one of the older members of the class responds to Miss Caroline's inquiry about what Burris has said. He explains that Burris is "one of the Ewells, ma'am....They come [the] first day...and then leave." Apparently, they are coerced by the truant officer who threatens their parent with arrest by the sheriff; however, she has despaired of trying to make them attend all the time. So, teachers are instructed just to mark them absent from then on.
"But what about their parents?" asks Miss Caroline in genuine concern.
"Ain't got no mother," was the answer, "and their paw's right contentious."
Evidently, the sheriff is too busy to be able to contend with Bob Ewell, or, perhaps, he does not wish to waste his time constantly arresting him for his children's delinquencies, knowing that the children will cause problems every time they go to school, anyway.
In all reality the Ewells are considered the lowest of the low in the book and the truant officers are just happy enough to get them there on the first day of school.
because they are lazy and dont care about education.
Because they are very poor and can't afford the work time that would be lost from going to school. The Ewells only attend school for 1 year. This explains why Mayella and Bob Ewell are not that intelligent nor speak proper English. This also explains why Burris shows disrespect toward Miss Caroline because of the fact that he could care less about school, let alone teachers.
The truancy lady eventually gave up on Burris and the other Ewells, as it was clear they came in only for the first day of term and then never bothered showing up.