The Importance of Lesson Planning

Lesson planning in science is especially important for a number of reasons, but first and foremost, is to keep all of our students as safe as possible.  There are a lot of instruments, supplies, and tools that are present in the science classroom that could potentially cause harm to students if they were to be used improperly, so safety should always be a teachers top priority when conducting any sort of science experiment with his/her students.  If you have a lesson plan laid out in front of you, then the experiment should run smoothly because you would have thought through all of the different possibilities of distractions and difficulties.  It is important that the teacher is prepared for the lesson he/she is about to teach, especially in a science classroom, because there is an increased chance that the experiment will not go as planned, and that there will be a need for some sort of backup plan or extension activity to help prove the point the original experiment was trying to make.
In class, we watched a video clip of an elementary school teacher named Sarah who tried conducting an experiment without ever trying the experiment on her own, and without even studying up on her content knowledge to be sure that she knew what she was talking about if something were to happen and her experiment were to fall apart, which it undoubtedly did.  Her biggest mistake was telling her students that she "did not know" when the experiment began to fall apart, and she started getting frustrated because she could not answer the questions her students were asking of her.  I think this exemplifies the importance of having an extension activity planned that you can refer to if all else fails, because let's be honest, not all science experiments are going to go exactly the way we planned them.  There are going to be times when the teacher will have no choice but to make the executive decision and stop the experiment in its tracks if it is not working in order to keep from confusing his/her students, or to maintain that high level of safety that is so extremely important. 
 I think that by using a lesson plan, teachers are able to get a much more accurate sense of how long an experiment is going to take, and what types of problems could potentially come up that would make the experiment extend for too long.  It is important for a teacher to keep an eye on the clock when conducting a science lesson because the students will be having fun and will not want to stop, so if the lesson is going to take longer than the time that has been allotted for science, the teacher needs to be aware of that so that he/she can make changes or extend the lesson over a few class sessions if necessary.  Writing and following a lesson plan will help teachers stay on track, and will help them stay within their somewhat limited time frame.  Experiments don't always run as smoothly as we would like them to, so I would highly recommend any teacher to refer to a lesson plan no matter how long they have been teaching, even if they feel they have mastered the material or have made this experiment work before in the past with no issues.