All too often schools put an intervention in place and it continues to be offered without any evaluation of whether it is successful. Program interventions have an impact on school resources, staffing allocations, and master schedule design. More importantly, they have an impact on the students who are in them. You need to ensure that any program intervention is meeting the needs of students by meeting whatever student achievement goal you set for it.
In order to evaluate a program intervention, you need to be clear on why the program was initiated. What was the program intended to do? What criteria were used to place students in the program? Were students reading below grade level and you were trying to move them to grade level? How much below grade level were they reading? If you have not clearly articulated what the goals of the intervention program are, you will not be able to evaluate it.
You will need to determine what evidence will demonstrate that students have met the goal. Will you use a specific assessment? If so, what must a student score to meet your goal? When teachers know the end goal in advance, they are more likely to plan instruction with that goal in mind and to monitor student progress against that goal.
The next thing you need to do is collect baseline data on where students are performing in relationship to the goal so that you can monitor progress against it. Unless classroom grades are reflective of student attainment of content standards, they will not be useful in determining student achievement progress on instructional goals.
You will also want to put some benchmarks or milestones in place against which the teacher can monitor whether students are making acceptable progress toward the end goal. It is only by monitoring student progress that the teacher will have any information to use in planning appropriate instruction. The benchmark data will inform the program evaluator whether changes need to be made in the middle of the year. The summative assessment at the end of the program will tell you whether the program was effective in meeting its goal.
When intervention programs are planned with the end in mind, the evaluation process is not difficult. When you inherit intervention programs that have not been planned with any end in mind, you often find that the teacher and students are unclear what the end goal is and have not collected baseline data against which they could chart progress.