The California Department of Education makes all of the data necessary to produce this chart, though a few steps are involved.
This is the type of chart we prefer
This example: mathematics performance at the San Jose Unified School District.
• Any result above zero is proficient; below is not proficient. • There is a 99% chance that results will remain the same in coming years, which is to say, between the Upper and Lower Control Limits (the gray lines).
Some helpful things about this chart:
It shows the scale! The highest possible score is 200, the lowest is -300. Zero is the minimum standard.
It shows the average.
It clearly shows there is little change. The Upper and Lower Control Limits are three (3) standard deviations away from the average.
This means that in subsequent years, if the system doesn't change, there is a mathematical likelihood of 99% or more that the results will remain between these control limits.
In other words, this chart shows what the follow-the-schedule method "wants". NOT what teachers want. NOT what you want. What the system wants — the system being Taylor's follow-the-schedule method.
In summary, this is a very useful chart! It shows there is no improvement happening in mathematics performance in the San Jose Unified School District -and- there is an extremely small chance of future improvements if San Jose Unified doesn't change to a method which "wants" something different.
This is another type of chart.
San Jose Unified School District mathematics performance
Ed-Data has produced a beautiful chart directly from numbers provided by the California Department of Education (CDE). https://www.ed-data.org/district/Santa-Clara/San-Jose-Unified
The data which feeds this chart comes from the following table, which likewise can be found here at Ed-Data. The numbers in this table come directly from CDE. For example, "20 %", the first number in the table below, comes from line number 2,703,729 under the column Percentagestandardexceeded in this data table for the year 2015.
Some unhelpful things about this chart and data:
While the above bar chart and table do provide quite a bit of information, it is never-the-less not very informative.
It does NOT show the scale!
It does NOT show the average.
It does NOT clearly show that there is little change. There is no predictor such as an upper and lower control limit.
In summary, looking at this chart, it is not clear how little improvement is actually happening in mathematics performance in the San Jose Unified School District.