You cannot write excellent performance objectives in a vacuum. Before writing your lesson plans, consult the teacher's edition of your curriculum to ensure that you have the same goals. In addition, some schools have site-based initiatives regarding performance -- particularly in relationship with standardized tests -- that may drive your lesson-planning. You should also consider district-wide goals, state standards and the plans of your teaching team when writing your performance objectives.
Backward planning is essential to effective teaching. Focus on your ultimate instructional goals for the end of the year; these goals will drive your shorter-term objectives for the semester and units. At this level, the objectives will be more general, allowing for changes in your pacing, focus and direction depending upon students' learning styles and their progress. After you have general unit goals outlined, break down your current unit into its discrete lessons and its associated performance objectives.
Make your objectives specific and focused on observable behaviors. Objectives stating that students will know, observe or discuss something are too general to measure well. Use active verbs, exact language and specific tasks to write effective performance objectives. You may ask students to provide examples demonstrating a hypothesis, demonstrate how to perform a task, identify patterns, argue the merits and disadvantages of a particular practice or conduct an experiment to show specific results.
Your objectives should cover the range of cognitive performance as outlined in Bloom's Taxonomy of Educational Objectives. The lowest level focuses merely on recall. The next level involves showing proof of comprehension. The next level, application, requires students to use a rule to show examples. The following level is analysis, or the ability to show relationships. Next is synthesis, the act of creating a new element from existing elements. The task associated with highest-order thinking is evaluation, the ability to justify a conclusion based on disparate criteria.