Teachers are very skeptical about new teacher evaluations tied to student achievement test scores.
There is a fear that one bad year (the one where you had that one "really bad" kid that spoiled everything for your classroom) will ruin any gains you may have made in your own evaluation process. We've found some tools to help you stay ahead of things. You need to document your classroom successes. There's an accountability notebook approach at the link below. It gives you a way to keep all your evaluations and assessments in one place. There's a book with it that provides complete instructions for collecting and documenting student (and your) work. There's a chapter on using technology (basic step by step) to help in the process, all using free software you already have. It's very much worth the cost.