Like all educators, science teachers rely on substitutes to lead their classrooms when they have to take a day (or more) of leave. In a recent anonymous NSTA Reports poll, 46.8% of participants reported needing a substitute for their classroom three or four times a year, with 28.6% reporting they depend on substitutes five or more times annually and 23.9% only once or twice a year. All reported leaving lesson plans for substitutes ahead of a planned absence, and 75% report maintaining “emergency” lesson plans for an unplanned absence. Most (77%) report that substitutes usually followed the plans.

Nearly 87% say they take steps to prepare their classrooms for a substitute ahead of a planned absence. Educators say they leave seating charts, set up labs, check the room’s organization, “label everything,” lock up all lab equipment, or “hide materials that may be stolen or damaged.” Eighty-four percent reported preparing their students for a substitute: many by reviewing class rules, expectations, and agendas.

Few (8%) report substitutes typically have a background in the subject matter, and a majority (65%) don’t get to approve or screen the substitutes that will teach their classes.

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Here’s what science educators are saying about the challenges of having a substitute:

Having them teach new content is scary, especially since each class coming in that day has its own atmosphere for learning. I’m afraid things will not be taught with the same passion that I teach them with.—Educator, High School, Indiana

You can’t leave a lesson and expect it to be taught, but at the same time, it’s hard to give up valuable teaching time.—Educator, Elementary, Washington, D.C.

Abuse and neglect of my workspace [has occurred].—Educator, Middle School, Maryland

When the substitutes I trust are not available and I have to just put the job out there for any sub to grab, I get worried that I’ll get the sub who sits on [his or her] phone all day and doesn’t follow the plans/help.—Educator, Middle School, Michigan

Unknown background [of the sub is typical]. I must leave a boring lesson. Something anyone can do…I can’t have students do an activity because I don’t know the background of the teacher. I use lots of technology in my lessons, but I can’t leave the same type [of lesson] for a sub.—Educator, Middle School, California

You aren’t entirely sure if students are getting what they need out of a lesson. Also, you can’t be 100% sure the lesson will actually get completed.—Educator, Middle School, Connecticut

Having the material correctly taught [isn’t guaranteed].—Educator, Middle School, New Jersey

They do not have a background in science. And I am not able to have labs or activities planned when I am absent.—Educator, High School, Kansas

I cannot expect them to teach science because they do not have the training and expertise to conduct activities with an awareness of health and safety in the science classroom.—Educator, Elementary, Wisconsin

[It’s unknown w]hether or not we will actually have a dedicated sub or if there will be other teachers covering a particular class. I could have six different people monitor my classes. There are times that one class may be covered, but others will end up in the auditorium with several other uncovered classes and nothing academic is able to take place.—Educator, High School, New Jersey

Having to skip labs or adjust activities when I can’t get a sub with science background.—Educator, High School, Illinois

Writing the plans is very time consuming. Every step has to be explained, and that takes a lot of time. Making an answer key and practice problems is time consuming. It’s not enough to say “practice rounding numbers up to the nearest thousand;” you need concrete examples and answers. Subs often don’t follow the plans. They skip steps and don’t insist that students complete things. Subs can have terrible classroom management, and that leads to problems when you return. Subs don’t clean up or ask the kids to clean up.—Educator, Elementary, Massachusetts

Holding students accountable for what did or did not happen while I was out.—Educator, High School, Washington

Unfamiliarity with technology; late arrivals (not arriving before students arrive means no time to read plans or prepare); our district pays the worst sub wages in the county; subs don’t seem to have intuitive behavior management skills, so problem behaviors escalate; lesson plans need to be “dumbed down” significantly, or lesson time is wasted because the sub made changes to the plan.—Educator, Elementary, New York

Finding ones with good classroom management [who] can follow directions [is challenging].—Educator, High School, New York

Having a sub who doesn’t “believe” in science. I had one—for a two-day absence while I was at a conference—try to convince my students that climate change wasn’t real, and scoffed though the entire video clip and reading the students were to complete.—Educator, Middle School, Connecticut

Not knowing exactly what happens in my room throughout the day. Substitutes do not always leave the best or most detailed notes. If you send a student out for any reason, I need to know why.—Educator, Middle School, Michigan

How much to prepare for them…can they fill in the spaces of a general lesson outline?—Educator, High School, British Columbia, Canada

I just don’t like putting my job in someone else’s hands!—Educator, Elementary, Texas

All of it [is problematic]. There’s someone invading your space! I’ve had substitutes [who] have left my classroom a mess…I’ve had subs that have yelled very rude things at my students. I usually just have my subs show movies. They don’t know my subject or the students. It’s just easier to show movies. And that way, there’s less of an aftermath to deal with.—Educator, Elementary, California

Are they technologically competent? Do they have enough content knowledge to respond to student questions? Will they follow my lesson plan to the best of their ability?—Educator, High School, Hawaii

As a control freak, not having control of what is done in my classroom.—Educator, High School, Maine

Classroom management issues—the room is torn apart, and the assignment is not distributed.—Educator, High School, Washington, D.C.

Content knowledge and ability to help the students with high school science concepts [is important].—Educator, High School, Illinois

Getting everything prepared, and trying to think of anything they might need or what could possibly go wrong and trying to prevent it takes up a lot of time. Our school requires a sub notebook. Setting it up in the beginning takes time, but it’s really helpful once it’s done.—Educator, Middle School, Oklahoma

Not all of the subs are respected by the kids. We have a sub shortage in our area, so when we are out sick, many times other teachers are losing planning time to sub for me.—Educator, Middle School, Pennsylvania

Creating lesson plans and not knowing who my sub is and then praying that [he or she] will follow the plans.—Educator, Middle School, Iowa

Creating lesson plans that are self-standing so that if my sub has no knowledge of science, which is typical, the students can still move ahead.—Educator, High School, Minnesota

Developing lessons that the sub can handle and [that] tie to the concept being taught at the time. I do not want it to be a wasted day.—Educator, Middle School, California

Every person handles things differently. Subs tend to be more lenient with discipline in the classroom. Some subs will work hard and walk around to make sure students are doing what they are supposed to, as well as assist the students. Some subs just sit at a desk and do nothing, letting the students run wild.—Educator, Middle School, High School, Pennsylvania

Finding a competent substitute for an extended period of time [is difficult].—Educator, Institution of Higher Learning, Missouri
Finding activities that are suitable for someone who does not necessarily have a science back ground [isn’t easy].—Educator, High School, Nevada

I feel that it is too dangerous for the substitute to do labs, so students miss out on hands-on activities. The exception is when I had a long-term substitute [who] had a background in teaching science.—Educator, High School, West Virginia

I never have a lab scheduled for that day. There are way too many safety concerns, and a background is needed to know that what they are doing (or not doing) is correct and will not put anyone at risk.—Educator, High School, Illinois

It is difficult to maintain an inquiry-based classroom with a substitute.—Educator, High School, Nebraska

It is so much more work to be absent…I’ve returned early to find the sub with his feet up on my desk reading the newspaper and students doing whatever. I’ve also had a sub [who] doesn’t speak or read English.—Educator, Middle School, Texas

Lack of science background. Lack of classroom management skills. The one substitute teacher that takes classroom supplies—copy paper, file folders, tape, stapler—[without permission].—Educator, High School, Florida

Lack of support for the sub [occurs] in our school. Some students tend to behave horribly and take advantage. Only repercussion may be from teacher when they return.—Educator, Middle School, New Jersey

Making sure I have all of the details spelled out. I once had a sub think the activity was too boring the way it was supposed to be done, so she let the students do whatever they wanted with the materials. Luckily there weren’t any chemicals that [could have] had bad interactions [when mixed] out.—Educator, Middle School, Iowa

Most subs cannot help students with physics problems.—Educator, High School, Pennsylvania

No matter how hard I try to make my lessons self-explanatory and easy to follow, I end up needing time before and after a lesson to make sure kids understood the material. Often sub days lead to misconceptions and missed concepts. I also have to leave detailed notes on kids so that there aren’t behavior problems. The subs in my building do not trust kids and seem to not even like teenagers, so they rarely give kids what they need to be successful unless it is explicitly written down.—Educator, Middle School, Wisconsin

Not being there to answer questions or follow up with student understanding [bothers me].—Educator, High School, California

Not following the detailed plans I spent months preparing [before] maternity leave. I had to reteach an entire unit.—Educator, High School, Rhode Island

Planning something a non-science person can teach [is typical].—Educator, Middle School, Nebraska

Subs rarely follow lesson plans at my school or reinforce class expectations and norms. I have had class materials stolen or damaged while I have been out.—Educator, High School, Michigan

The fact [is] my district only pays $85 a day, so it’s hard to even get a sub to cover classes, much less a qualified science teacher.—Educator, High School, Colorado

[I dislike t]he time wasted planning “sub-proof” lessons and missing instructional time with my students.—Educator, High School, Michigan

There are not enough substitutes available, so when calling in an absence, I do not know if the school will actually find someone.—Educator, High School, Michigan

They do not know lab safety: They do not have any knowledge of the equipment and chemicals that could be in the room. They also bring coffee and a book most times.—Educator, High School, New Jersey

They do not know the structure of the course; they do not know content well enough to help students if they have questions. I almost always schedule a test for a planned absence so that I don’t lose instructional time, since subs cannot be relied upon to provide direct instruction or even supervision.—Educator, High School, Virginia

Not knowing how they are going to treat my students [troubles me]; the majority of my class is special [education]/behavioral.—Educator, Elementary, Alabama

We are on an alternate day block, and it is important that a whole block doesn’t get wasted. The biggest challenge is trying to design the lesson so that the students can get the most out of the lesson and know they are capable of forging on when I am not there. Once this classroom culture is established, it is not as difficult to be gone (usually at trainings/meetings).—Educator, High School, Wisconsin

[I mind w]hen they do not follow plans as written. Even small changes are difficult to account for.—Educator, Middle School, Nebraska

This article originally appeared in the November 2016 issue of NSTA Reports, the member newspaper of the National Science Teachers Association. Each month, NSTA members receive NSTA Reports, featuring news on science education, the association, and more. Not a member? Learn how NSTA can help you become the best science teacher you can be.

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