Another way of looking at dropout rates is to note the grade population each year. The picture is similar to what we have seen looking at one cohort over four years. The number of students is highest in grade 9, then drops precipitously by grade 10, and drops further in grades 11 and 12. One factor to note is that most students have their 16th birthday around the 10th grade, and thus reach the age when it is legally possible for them to drop out. This of course does not address the reason why they make that decision, nor why this is different for Trenton's young people than for those in communities like Montgomery. This figure shows the statistics for four years, in which the decline is evident and similar each year. Notice also that the total student enrollment is also declining from year to year. (Click on the graph for full size.)
The fact that the total population at TCHS has dropped by almost 20% over the last four years is another mystery, and it bears examination because it probably is related to our primary question. The reasons for the overall change may reflect reasons for the dropout rate, so we want to understand why it is happening. Pending further study we are limited to speculation and suggestions, but this should help define the right questions to ask.
The overall decline seems too large to be a simple matter of changing population in Trenton. There have been shifts in the ethnic balance in the city, with relative increases in the Hispanic population, but this is not an obvious explanation for the TCHS numbers declining so radically. Are the students dropping out earlier, or going in greater numbers to other schools? We don't know the answers to these questions, but they are important to our mission to improve the system. We want to learn what the determining factors are, and how to encourage students to stay in school, learn the skills for successful adulthood, and graduate with solid credentials.
The most compelling suggestion comes from comparing the populations by grade level. It is important to observe that the total decline is driven by dropouts from the 9th to 10th grade. The 9th grade population plummets by 33% over this four year period. There is an irregular but downward trend in the 10th grade, and a small decline also in the 11th grade. But we see almost no change in student numbers in the senior year. In other words, the overall decline apparently is a function of conditions affecting younger people. Those who are going to drop out of the system do so early.