How to Write a Lab Report

How to Write a Lab Report
STEP 1 – State the Question
 The first step to writing a lab report is to tell your
audience the question you are trying to answer.
 For our lab, the question was “How does
temperature affect how long it takes a Skittle
to dissolve?”
STEP 2 – State the Hypothesis
 The next step is to state your hypothesis.
 If you are in 5th or 6th grade, you wrote an
“if…then…” statement on your page.
 If you are in 7th or 8th grade, you wrote an
“if…then…because…” statement.
STEP 2 – State the Hypothesis
 Poor example:
 I think the Skittle will dissolve more quickly in warm water.
 Good example:
 If I put one Skittle in cold water and one Skittle in warm
water, then the Skittle in the warm water will dissolve more
quickly (because…)
STEP 3 – Summarize the Procedures
 This step should be written so that a new person
could repeat the experiment. This should be several
sentences long.
 Include the materials you used and all of the steps
you followed. Refer to your lab sheet from yesterday
for this information.
STEP 3 – Summarize the Procedures
 Poor example:
 In this experiment we used candy, cups, and water. First we
put cold water and warm water in the cups. Then we put in a
Skittle and waited for it to dissolve. Then we did this two more
STEP 3 – Summarize the Procedures
 Good example:
In this experiment we used Styrofoam cups, Skittles, hot and cold
water, popsicle sticks, a measuring cup, and an optional timer.
To begin the experiment, we put 150 mL of cold water in one cup and
150 mL of warm water in the other cup. At the same time, we
dropped a Skittle into each cup and began stirring with our popsicle
While we stirred, we kept track of time until we saw that all of the
color had dissolved from the Skittle. We stopped stirring and
recorded the time in our chart.
We emptied our cups and began the process again with fresh water
and new Skittles.
We did this a third time to have the most accurate results.
STEP 4 – Data (tables, charts, etc.)
 For this step, you will state your observations.
 Depending on the experiment, this step could be
short or long.
 If you have a graph or picture, you can copy it onto
your lab report or staple it to your lab report and say
“See attached sheet”.
STEP 4 – Data (tables, charts, etc.)
 Poor example:
 I watched the water change colors. We made a graph.
 Good example:
 During this experiment, I saw that the water began to turn into
the color of the Skittle. The Skittle lost its color and turned
 See attached sheet for an additional chart and graph.
STEP 5 - Conclusion
 This will usually be the longest part of your lab report.
 It should be written in paragraph form.
 It should restate your hypothesis and whether it was
correct or not. It should also tell why you think it was
correct or not.
Next, you should discuss your data. If you took
measurements, like time, share those results.
7/8 – state independent, dependent, and control
If there are any important vocabulary terms, you should
discuss those as well.
To end, state what you could do to improve or change
this experiment next time.
STEP 5 - Conclusion
 Poor example:
 I learned a lot in this experiment. My hypothesis was right
because the hot water dissolved better. It always went faster in
the hot water. I don’t have any idea why that happened, but it
was cool. I wouldn’t change anything about this experiment.
STEP 5 - Conclusion
 Good example:
 In this experiment, I wanted to figure out how temperature
affects the rate at which a Skittle will dissolve. My hypothesis
was if… then… (because…). I was surprised to find out that I
was wrong, because when I did the experiment I found out that
hot water actually makes a Skittle coating dissolve more
quickly. I think this might happen because hot water makes
particles move more quickly.
 When I did this experiment, it took 24 seconds, 28 seconds,
and 27 seconds for the Skittles in the cold water to dissolve. It
took 38, 36, and 33 seconds for the Skittles in the hot water to
STEP 5 - Conclusion
There are always variables in an experiment. Some of my
control variables were that I used the same color Skittles, the
same type of cup, and the same amount of water. My
independent variable, or the variable that I changed in the
experiment, was the water temperature. The dependent
variable, or the variable that I measured, was the amount of
time it took to dissolve.
If I did this experiment again, I would use even hotter water to
see if this made a difference. I could also see if it took longer
for different colors to dissolve, or I could use different types of
candy, like M & M’s, to see their results.