In Delaware, about 1924, teachers were classified in four grades of certification.
First Grade - Completed two years of Normal school after graduating high school.
Second Grade - Completed four year of high school plus six weeks of professional training and passed elementary school subjects.
Third Grade - Did not graduate from high school but completed six weeks training and past the examination in elementary school subject.
Provisional Certificate - passed a portion but not all of the elementary school subjects and due to the shortage of teachers are temporarily engaged in teaching.
In that time period the pay was about $1,000 for 180 days of teaching for a First Grade certificate.
A second grade teaching certificate would earn $800 for 180 days of teaching.
A third Grade teaching certificate would be valued at $600 for 180 days of teaching.
A Provisional Certificate would be about $500 for 180 days of teaching.
The one room rural school house is where the third and provisional teachers went. Because of agriculture demands on families where children were needed to help on the farm the rural school teacher rarely had 180 days as they started late in the year and closed down early in the spring so their pay was prorated over about 160 days.
Prior to the early 1920 a rural school teacher was paid between $38 a month to $60 a month and usually only worked 7 months. The average pay being $270 a year. Even worst the pay was partly paid by the state and partly paid by the school district. If the school district did not set a high enough tax rate to cover their share of expenses the teacher might receive for their last pay check an IOU to be paid when the tax collection cycle took place The Millsboro school district and the Millville school district was particularly bad for this and in 1919 were sued by the teachers for back pay from the 1916-17 school year.