A Way to Solve a Problem

Day 1

Write in your agenda: I can ask questions and form hypotheses that can be

explored through scientific investigations.

Activator: In your agenda write a sentence or two explaining what you think this picture represents.

Inquiry: an investigation; the testing of an idea in a search for knowledge

Observation: What you actually saw happen during an experiment.

1. The balloon on the bottle containing Nutrasweet did not expand.

2. The plant that received SuperGro fertilizer grew 4 cm. in the first week.

3. The ducks fed in the shallow end of the pond 85% of the time.

Examples of Other Laboratory Related CRCT Questions

The students in Mrs. Padgett’s class wanted to learn about the ducks in a pond near the old middle school. Which question could the class answer by making observations at the pond?

A.Where do the ducks go when they migrate?B.Which part of the pond do the ducks use for feeding?C.How many ducks were in the pond last May?D.How many years have certain pairs of ducks been together?

Inference: logical conclusion drawn from available evidence and prior knowledge; inferences are often made from observations and attempt to explain what we see.

When Jordan studies for a test, she always gets an A (this represents what you already know about Jordan.) On the last test, Jordan scored a 70 (This is what you observe at this time.) What inference can you make?

Jordan did not study

The geological boundary known as the “Fall Line” in Georgia is believed to be the area where the ancient coastline existed. What types of scientific data might have first led scientists in the 1800s to infer that the ocean at one time covered half of Georgia?

A. Ancient writings found on stone tablets dating over a million years old.B. An abundance of fossil remains of ancient sea-dwelling creatures like clams that are found far from the modern day coastline.C. The remains of ancient boats estimated to be 200,000 years old that were preserved in mud near Macon.D. Photographs taken by aliens who are capable of traveling back in time.

A lab report for a plant experiment contained the four statements below. Identify whether the statement is an observation, hypothesis, or inference. 1.All of the plants bent toward the small light source. observation2. Each of the plants grew less than 2 cm. observation3. Lack of light caused the plants to grow at a slower rate.

inference4. Several of the plants have yellow leaves.

observation

It is a series of steps a scientist takes to identify a question, develop a hypothesis, design/carry out the procedures to test the hypothesis, and document observations and report findings.

In other words, it’s a way to solve a problem.

Step 1 State the problemStep 2 Conduct Research Observations can be made in many different settings:

a. lab investigations b. computer models c. fieldwork

3. Form a hypothesis, or a prediction that can be tested. It is an educated guess. Your hypothesis should be based on research. You should always be able to give reasons why you chose your hypothesis.

Examples of a Hypothesis

•Yeast will not feed on sugar substitute.

•Tomato plants that receive MegaGro fertilizer will produce larger fruit.

•The Energizer brand battery will last longer than Duracell in devices like digital cameras.

Example from OAS

Which is a hypothesis?a.Five earthworms died when the soil became too dry.b.Earthworms have a mucous covered outer surface.c.Heavy rain causes earthworms to move above the ground.d.What will happen if an earthworm is cut in two?

Letters a and b are observations. D is a question.

C is a hypothesis

Euglena are single-celled organisms. The flagellum helps the organism move through water. Euglena are similar to plants in the way they obtain their food. Nina kept several euglena in a glass jar. She wondered what would happen if she covered the top half of the jar with black paper and placed it in sunlight. Which is the best prediction of how the euglena will respond to the change in the jar environment?

A. Most of the euglena will move to the bottom half of the jar. B. Most of the euglena will move to the top half of the jar. C. The euglena will spread out evenly throughout the jar. D. The euglena will move back and forth between both halves.

Example from OAS

Day 2

Write in your agenda: I can ask questions and form hypotheses that

can be explored through scientific investigations.

Science Starter

1. Explain the difference between an inference and prediction. An inference is when you explain something you observe. A prediction is a forecast of something to come.

2. Explain how a qualitative observation is different from a quantitative observation.

A qualitative observation deals with descriptions without numbers. Quantitative describes something using and amount.

Activator:

Have the students close their eyes and slowly read the three sample observations

4. Test the hypothesis w/ an experiment a. A variable is something in an experiment that can change. b. A control is the standard of comparison in an experiment; it cannot change

VARIABLES Trial 1 Trial 2 Trial 3Amount of water

½ cup ½ cup ½ cup

Water Temp 80°F 120°F 160°FAmount of Yeast

1tbsp 1tbsp 1tbsp

Amount of Sugar

2tbsp 2tbsp 2tbsp

Amount of Flour

1 cup 1 cup 1 cup

Experiments contain variables. For example, in the following experiment Jose wants to determine how water temperature affects the rate at which yeast breaks down sugar to make bread dough rise:

The amount of water, water temperature, yeast, sugar, and flour are all variables.Which variable is the only variable that changes in each trial? _______

Independent Variable – something that is changed by the scientist◦What is tested◦What is manipulated◦The one and only variable you will change during an experiment.

Constants

The other variables do not change. They are constants.The constants in an experiment are all the factors that the experimenter attempts to keep the same.

VARIABLES Trial 1 Trial 2 Trial 3

Amount of water 40 ml per day 40 ml per day 40 ml per day

Light Source Color red green yellow

Light Distance from Plant

20 cm 30 cm 40 cm

Hours per day of light

6 hours 6 hours 6 hours

If more than one variable changes, the trials will not be reliable. What is wrong with the variables for this experiment measuring the effect of different colored lights on plant growth?

The dependent variable is part of the results. In the trials above measuring the effects of water temperature on the rate at which yeast breaks down sugar, the dependent variable would be the size of the bread dough after it had risen.

Dependent Variable – It is what you measure to compare the results of your tests.

◦It is the data collected during the investigation.

◦It should be able to be charted or graphed.

ControlIt is what you will compare your results to; usually

just the absence of the independent variable.

The control group is exposed to the same conditions as the experimental group, except for the variable being

tested.

All experiments should have a control group. Allow for a “fair test”. In the experiment mentioned on the previous slide to observe the effects of different colored lights on

plant growth, the control would have all the same variables but the light source would be a normal full

spectrum growing light that produces light similar to that of the sun.

What is the independent variable in this experiment?

  Bottle A Bottle B Bottle C

Amount of water 12 fl. Oz. 12 fl. Oz. 12 fl. Oz.

Type of heat source 9 in. electric burnerset on “high”

9 in. electric burnerset on “high”

9 in. electric burnerset on “high”

Water temperatureat start.

60 deg. F 60 deg. F 60 deg. F

Amount of salt 3 tbsp 6 tbsp 9 tbsp

•Jody wants to conduct an experiment to see if adding salt to water will make water boil faster.

The amount of salt used.

Archibald wants to conduct an experiment to determine which of his three candles burns the longest. One is made of beeswax, another soy wax, and the third paraffin wax. Each candle has a tapered shape, is 8 inches in height, and weighs 6 ounces. What is the independent variable in this experiment? The type of wax.

What is the independent variable in this experiment?The amount of light each sample was exposed to.What inference can you make from the data in this table?Light was not necessary for a seed to germinate.

Ages of the students◦Different ages were tested by the scientist

The time it to put the puzzle together◦The time was observed and measured by the scientist

What was the Constant? The puzzle

Sizes of nails◦These were changed by the scientist

Number of paper clips the magnet could pick up.

Constant:Battery, wire

Intentionally manipulated

ControlledCause

Intentionally left alone

MeasuredEffect

5. Make observations and collect data

6. Draw conclusions a. hypothesis supported = repeat experiment b. hypothesis not supported= revise hypothesis

7. Share your results

1.State the Problem2.Conduct Research

3. Form a Hypothesis4. Test your Hypothesis with an Experiment

5. Make Observations and Collect Data6.Draw Conclusions

7. Share Results.

The independent, or manipulated variable, is a factor that’s intentionally

varied by the experimenter.John is going to use 25g., 50g., 100g., 250g., 500g. of

sugar in his experiment.

The dependent, or responding variable, is the factor that may change as

a result of changes made in the independent variable.

In this case, it would be the size of the loaf of bread.

Mr. Krabs created a secret ingredient for a breath mint that he thinks will “cure” the bad breath people get from eating crabby patties at the Krusty Krab. He asked 100 customers with a history of bad breath to try this new breath mint. He had fifty customers (Group A) eat a breath mint after they finished eating a crabby patty. The other fifty (Group B) also received a breath mint after they finished the sandwich, however, it was just a regular breath mint and did not have the secret ingredient. Both groups were told that they were getting the breath mint that would cure their bad breath. Two hours after eating the crabby patties, thirty customers in Group A and ten customers in Group B reported having better breath than they normally had after eating crabby patties.

1. Which people are in the control group?Group B – they ate the regular mint.

2. What is the independent variable?The type of mint.

3. What is the dependent variable?The number of people with bad breath.

4. What should Mr. Krab’s conclusion be?That his breath mint works. 30/50 people agree!

5. Why do you think 10 people in group B reported fresher breath?They were told that they had received the new mint. Their response may have been influenced by their emotions.

SpongeBob noticed that his favorite pants were not as clean as they used to be. His friend Sandy told him that he should try using Clean-O detergent, a new laundry soap she found at Sail-Mart. SpongeBob made sure to wash one pair of pants in plain water and another pair in water with the Clean-O detergent. After washing both pair of pants a total of three times, the pants washed in the Clean-O detergent did not appear to be any cleaner than the pants washed in plain water.

6. What was the problem SpongeBob wanted to investigate?

How to clean his pants.7. What is the independent variable?

Whether or not he added laundry detergent.

8. What is the dependent variable? The cleanliness of the pants.

9. What should SpongeBob’s conclusion be?

That the Clean-O detergent does not work any better than water.

15. Identify the following:Control- Krusty’s usual itching powderIndependent Variable- The type of itching powderDependent Variable- The amount of time someone itches

16. Explain whether the data supports what the advertisements claim about the product.The advertisements are correct! They claim to cause 50% longer lasting itches than the usual powder. If the usual powder lasts 30 minutes, 50% of 30 is 15 minutes. 30 + 15 is 45 minutes of itching which is what the subjects reported