Science Buddies: "Ask an Expert"

Woops I just realized I posted this question in high school forum. My son is a 7th grader so I am posting here too.

My son's project is up and running and now his teacher (new to science fair) is questioning having "too many variables". He wanted this to be a comparison and complex test and set up 3 controlled experiments. WIthin each of these experiments he has the same one Responding and one Dependent Variables. The controls for all of the 3 experiments are the same except for the construction materials. We tried explaining this is One Science Project that has a total of 3 Controlled Experiments each with their own set of Variables (which happen to be the same except in construction). To make it more clear, he constructed a Residential Village. Experiment 1 is 2 Wood Frame Houses with Wood Roofs. Experiment 2 is 2 Wood Frame Houses with Tin Roofs, Experiment 3 is 2 Concrete Block House with Wood Roof. In each of these experiments one of the houses is "coated" with a special product and the other is not. In each of these experiments the interior cubic area is the same. His project is questioning whether the "coated" houses are more energy efficient than the noncoated houses (and by how much) AND which of these 3 construction methods are the most energy efficient when comparing all 3. His project has a purpose because his brother is trying to build a barn for his rabbits and wants it to stay warm in the winter and cool in the summer (our bigger problem in Florida).

We had read a lot before starting this and found that this is more than the judges require but as long as each experiment was done using Scientific Method this was OK?

Can anyone confirm and add comments. It is still possible to tweak this if it does not fall within guidelines but it will look very very simplistic when it is actually quiet complex and involved a lot of research into nanotechnology on his part.

Thanks,

Lisa Grady

Is it scientifically ok? maybe, assuming each experiment is sufficiently well controlled and there is an appropriate hypothesis, it may be viable.
Will it be hard to present and convey accurately? Most definitely.
Would I recommend presenting it? No.

The key to doing a great science fair experiment is coming up with a good hypothesis that is easily testable and can be well controlled and that the outcome is unknowable ahead of time.

IMO: If the hypothesis involves the coated vs non-coated behavior, then he should restrict the experiment to one construction style. If the hypothesis does not involve the coating, then comparing three different construction techniques will be far more difficult because the different materials have different properties in many different ways:
1) the way the materials are joined
2) the thermal mass of the materials
3) the ability to seal or ventilate the structure
It would be extremely easy to accidentially bias the result unfairly for the different materials case.

In some ways I agree with Craig, and in other ways I disagree.

I do agree that it will probably be difficult to keep everything the same across all experiments. At the same time though, he's also in 7th grade. Understanding the idea of the scientific method, doing an experiment, and realizing that the experiment was difficult to control, is a great lesson in learning, and that's what they want you to learn in middle school. If this were a high school project and the person really wanted to win at a competitive science fair, I'd probably tell them not to do it unless they figured out ways to minimize errors. But in middle school, when a student is just learning about the scientific method, making mistakes and learning from them is part of the process. And truthfully, there are a lot of other middle school experiments where it is also hard to control the different variables. While I think it is important that the students realize that some of the projects are actually much more complicated than they look, since they are in middle school, things do need to be simplified to their level, and that brings introduces some errors and other problems. We actually have similar "house" projects on the science buddies website that introduce other building materials, and to me, that means this more complex project should be ok to do. (Here is one of the projects, in case you are interested: https://www.sciencebuddies.org/science- ... p039.shtml)

I would talk to your teacher more about this. Does he/she care that the experiment is more challenging to control? There are certain things you could do to minimize the errors in the experiment, but it will still be tough to do a controlled experiment. But if you want your son to get a good grade on the project, unfortunately its normally a good idea to go with the teacher, even if you don't agree with them.

If anything, your son would learn a valuable lesson in learning to communicate a confusing topic. I think it is great that he is challenging himself in 7th grade and seems to be enjoying the project. If you think the quality of his work will decrease if he does all 3 experiments, then I wouldn't do it. But if the teacher lets him, he has enough time, patience, and energy to do a good job, I say try the more complex version, with a few caveats (described below).

Judges care about truly understanding the results in a scientific manner (so explaining what the coating does in scientific terms, and how each material's properties affect the results would be important). In 7th grade, the judges are not going to expect him to know complex equations and really advanced concepts, but he should still understand important concepts in a more general sense (i.e. this material has these four properties, this is how they should theoretically affect the inside temperature, and this is what actually happened and why). He needs to understand that it will probably be difficult to get accurate results, but at the same time, he can compare his results to what the research says, and see if he comes close. If he's able to explain why the experiment was difficult to control and how it might have affected his results, that should be fine for a 7th grader. If you think he has enough time and energy to not only complete the experiments, but also learn more about this information and understand it, and apply it to the results, then I think he should do it.

Here's what I would do:

-I would do one of the experiments
-Write up the report for one of them
-Do the rest of the experiments (if there is time)
-Add on to the first report (but keep a copy of the simpler paper).

This way, you will make sure you have enough time to complete at least one experiment. If you have more time, you do the other 2 (or 1, if that is all you have time for).

I would then ask the teacher to look at both papers, and grade according to the one he/she liked the best. Of course, it also depends on the teacher. Some teachers would love that the student put in so much effort, others might just see it as another paper to grade. If you think your teacher would hate the idea of grading two reports (maybe just ask them now, while you are deciding), then do the simpler version. If the teacher says no, and your son is reallly interested in this, he could finish the project to determine how to house the bunnies, but not write a paper for the rest of it.

I think this can be pulled off, but your son needs to realize it is going to take a lot of effort and perseverance. If he's really gung-ho about it, go head. He will need to be organized and do a great job of explaining the results. Comparison charts are definitely necessary so it is easy for people to quickly understand the overall results. Otherwise, stick to the simpler experiment.

Personally, I think it would be very interesting to see if one set of houses does better overall, and whether the coating gives similar results for each type of house.

That's my two cents. Sorry it was so long...more like "my $20"

Thanks so much for everyone's advise. We will let you know what we decide and how we end up presenting our results. He actually wanted to do a continuation from last years project, but the company that was producing the Nanotech "buckypaper" that he wanted would not release a sample because it is not patented yet. So this year's project is sort of a "hold-over" until he can do what he really wants to do from the prior year.

But thanks again to everyone.

OK we are exhausted. Building the concrete house was a bear and still wet of course. So after talking while we were working we have decided to go with one of the experiments. I guess all our work and building 6 structures is for nothing! (Or maybe he will figure out some way to use in a continuation project next year). Anyway, we decided to go with the Wood Frame building with the tin roof since this is more like an actual barn on a farm would be constructed (his real world application).

Our new question is this....we need some very fast data to hand in to the teacher by December 4 (she said we can then take out time to collect data before regional competition in February). Our structures are 2x2x2 and there are 2 of them. We can not rely on data from the outside temperature alone at this point because we do not have enough significant variation this time of year in Florida. For the "heated" portion of the experiment my son came up with one room in our house that has its own AC system. The temp could be turned up high and temp inside both coated/noncoated houses recorded at different times. WHAT ABOUT COLD TEMPERATURES? Anyone have any ideas how we could locate these structures somewhere at extremely cold temperatures so we could record data? I was thinking about a walk in freezer but do not even know who to ask about something like this. The thermostat in that one room in our house would probably only drop the temperature to 68 or so at a minimum and he is looking for lower temperatures than that. I am not aware of any rentable chillers of any kind. DOES ANYONE HAVE ANY IDEAS?

See my reply in your other thread.