I received the greatest compliment while sitting at the lunch table with a mixed age group of my students who are enrolled in the end-of-school-year camp. The children were playing a conversation-starter game they’ve developed of asking the lunchers to raise their hand if they fall into the named group (have a red lunch box, have an apple in their lunch, like to eat pretzels…). Then a five-year-old sitting next to me called out, “Raise your hand if you’re a scientist!” and all the hands went up.
What a gift to have confirmation that the science activities we did throughout the three years I taught him were seen as a process with the students as the central actors, and that all the children self-identify as scientists. Thank you to my students.

You didn’t mention the grade level of your new assignment. Some states have separate credentials or endorsements for teaching at the middle school level. Before accepting the position, check with the personnel/human resources director and your teachers’ association to be sure you are properly credentialed for this new assignment. When this documentation is in place, you’re ready to start the next chapter of your career.
There has been much research on the challenges faced by novice teachers. However, I know of very little research on what happens when veteran teachers change subjects or grade levels (an interesting dissertation topic for an education researcher?). A veteran fifth-grade teacher who is assigned to a first-grade class may struggle at first with the primary curriculum and the students’ maturity (or lack thereof). It’s a humbling experience as a veteran teacher to realize you may not have all of the answers right away in a new situation and that you’ll make some mistakes. On the other hand, as a middle school teacher who switched to high school, I already had a repertoire of strategies to deal with the ninth-graders everybody else complained about.
Your collection of lessons, assessments, and materials may no longer be appropriate, so you’ll have to spend time creating or adapting materials and lab investigations. Ask for a copy of the curriculum, textbook, and other resources to review ahead of time. If you change schools, you’ll have to get used to new schedules and get to know a new group of teachers. If you’re teaching a different subject, you may need to refresh your content knowledge. NSTA can assist with resources such as SciLinks and the resources on the NSTA Learning Center. As an NSTA member, you can access the journals’ online archives (and you may want to switch your print subscription, too, if you’re switching grade levels).
Veteran teachers are usually not required to participate in induction programs, but my district did assign “mentors” to teachers who changed schools, grade levels, or subject areas. It was helpful in a new assignment to have a go-to person to answer questions and share resources and information. Try to find a colleague who also changed teaching positions and pick his or her brain about what to expect from a different age group or in a new school.
Your experience gives you an advantage over a novice teacher. You already have a strong foundation in science, and you’ll be able to help students see the connections between science concepts. You’ll already know a variety of strategies for instruction, assessments, lab safety, and classroom management.
Some teachers are content to teach the same subject to the same grade level in the same classroom/lab for their entire career. I’ve found, however, that changing assignments was both personally and professionally rejuvenating. It forced me to learn new content and how to relate to different age groups of students. I learned new instructional skills and expanded my circle of professional colleagues. I loved working with the enthusiasm of middle school students, but I also thoroughly enjoyed the intellectual interactions with high school and college students. Reflecting on your question, I realized working in a variety of situations helped me feel even more “highly qualified” as an educator, beyond the official definition.
If anyone has any other suggestions to help Charlotte with the transition, please feel free to add a comment.