Sunday, March 16, 2014

Keeping a Lab Notebook and the Scientific Method


Thomas Edison kept LOTS of lab notebooks!
When you begin thinking about your science fair experiment you will want to get a composition book (the kind of notebook that is stitched together at the binding and won’t fall apart when you use it a lot) and keep all the ideas and thoughts you have about your project in it. Call it your “LAB NOTEBOOK” – it sounds so impressive and official! Don't put your name on the outside (science fair judges don't want to see your name when they judge), but do eventually include the title of your project on the cover so the book doesn't get lost. Number all the pages in the top or bottom corners and leave a few pages at the beginning for a "table of contents" - just like a chapter book or a text book. Each time you begin to write in your book, write the date and then go back to the table of contents and write the page number and what you are writing about on that page so it will be easy to find when you need it again.

You can put all of your ideas in this book, even if they end up not being what you decide to do for this science fair project. In the beginning you may not know what will work out and what won’t so just put everything in there. For example, maybe you are interested in why that volcano explosion thing we talked about before works but don’t know much about it yet – write it down as a possible idea.

The next step is to do a little research to find some information about the science that relates to your ideas. When you know a little bit more about those ideas you can begin to decide which can be made into experiments and how to do it. If you are still a young scientist and all that writing take a long time you might want to enlist the help of a “lab assistant” to help you keep your notes and make important experimental decisions, but the ideas should be yours. Back to our example of the volcano reaction… this section of your lab notes might be some information about why vinegar and baking soda react together to make a bunch of bubbles. What kind of reaction is it? (acid-base) Which part is which? (acid=vinegar, base=baking soda) What is in those bubbles it makes?(CO2) What is an acid anyway?(Ph level less than 7, edible things that taste sour are often acidic like pure lemon and lime juice) What is a base? (Ph level greater than 7, things that feel a little soapy or slippery when they are wet are often basic).
With an idea for an experiment and a little background information about the science all swimming around in your head you might be able to make a good guess as to the outcome of your experiment. This is called a hypothesis. In our example, knowing that the volcano reaction is an acid-base reaction and that vinegar is acid and that other acidic things are sometimes sour tasting might help you to decide what might happen when you react different things with baking soda. You might make the hypothesis that sour things like vinegar and lemon and lime juice will react to make bubbles and things that are not sour, like milk and water and soda won’t.

A lab notebook in its natural habitat, a lab bench.
Now comes the step that is the MOST fun, the experiments! Come up with different trials of your procedure. In our example we can mix a small amount of baking soda with a small amount of the liquids mentioned before. Each new combination is a trial and the measurements, conditions (the temperature, if you stir it or not, do you add the liquid to the baking soda or the baking soda to the liquid) and the results of the trial should all be recorded in the lab book. Even young scientists can record data by drawing small pictures of what happened or making x’s or check marks in a data table drawn by the “lab assistant” for either a positive result or a negative one – in our example, if the reaction made bubbles or not. The more original work done by the scientist the better – as long as it is within their ability level and does not overly limit their enthusiasm for the project.
experiment that will either prove your hypothesis right or wrong. Write down all the steps you follow to do each trial - this is your
Finally, go back and look at your hypothesis and the results of your experiments and see if you were correct or not. Make some conclusions about why it turned out as it did. In our example… well, I won’t spoil it for you so you can do those experiments yourself and see if I made a good plan or not. I will say that my hypothesis was not 100% correct, I will leave it to you to find the trial or trails that did not agree and figure out why (but please don't do this example as your science fair project, find one of your own design).

Keeping all your information in one place in a lab notebook helps you keep it organized and all together, keep accurate records of what you did and when you did it and helps you remember what the results were. For the science fair it also lets the judges see how hard you worked and all the great ideas you had along the way, as well as how well you are able to organize and think about your results (the data).

Good luck with your projects! Please let me know if you have any questions and don't forget to let me know what you will be doing by turning in a Science Fair Idea form before Spring Break - the forms and the folder to turn them in are on the book shelf near Mrs Buro's office in the Media Center.

Saturday, March 8, 2014

Finding an Experiment for Science Fair

What are you curious about?     



        What makes you  wonder
                                                                             
           What are the things that make you ask        
                 WHY? 

Those things can often make great science fair projects! Talk to the adult that will help you and look around on some of the websites I have recommended on the right side bar for ideas if there are just too many possibilities to narrow down. The next thing to consider is if you think you can make that interesting thing into an EXPERIMENT.

So what makes an experiment? There are lots of fun science activities that are NOT experiments. Making a 'volcano' explode with baking soda and vinegar is an awesome demonstration of some basic chemistry, but it is not an experiment. Learning a little about capillary action by watching colored water creep up a celery stalk is interesting, but not an experiment by itself. Picking up little pieces of paper with a drinking straw you have charged by rubbing with the paper wrapper looks like a great magic trick that is based on science, but it is NOT an experiment (it is a very old demonstration first described by an early Greek scientist named Thales of Miletus in 600 BC, but he used a rod made of amber and a piece of wool, not a plastic drinking straw and it’s wrapper!).

An experiment is a lot like a multiple part demonstration where each separate part has a lot of things that are the same – CONSTANTS - and one thing that is different – the VARIABLE. If you try the same thing with one condition that changes you can then see how the result changes. Let’s take the example of the volcano reaction I talked about before… that reaction creates gas – it is what fills the bubbles that make up the foam that spills up and out of the cup. What would happen if you used the same amount of baking soda (a constant) and changed something about the stuff you put in it? You could try different amounts of the same vinegar. In this case the vinegar itself is also a constant and the AMOUNT of vinegar is the VARIABLE.  Or, you could try the same amount of several different liquids… like white vinegar, milk, cider vinegar, soy sauce, lemon juice, lime juice, water. In this case the amount is a constant and the KIND OF LIQUID is the VARIABLE. The really fun part comes in when you see how the result of the reaction changes as the variable changes. You can record the results of your experiments and decide why you think the different conditions had the results they did. THAT is an experiment!

In the case of the capillary action in the celery stalks, different colors in water as shown in the picture probably would not be different enough to see a change. However, you could put one stalk in a cup of colored water in the refrigerator, one at room temperature, and one in a box warmed with a light bulb. You could then check on them at different times to see how far the dye had crept up the stalk. The different temperatures might make a difference in how fast the celery takes up the colored water. In this example what do you think the CONSTANTS are? What about the VARIABLE?

There are other things to think about when doing your chosen experiment, but the first step is to choose something you are curious about and decide how to make it into an experiment. There will be posts soon about how and why to keep a lab note book and go about figuring out a hypothesis, and things to keep in mind that will help you follow good experimental procedure. For now, get yourself a composition note book and start by writing down some ideas about things that make you wonder and how you might do an experiment with that idea or activity.  If you can't think of a way, ask for help from either an adult or by leaving a comment here or emailing me. I would love to hear what excites you and makes you curious.

Until next time... keep wondering!