1. The Mystery of Ocean Beach
This summer I found something unusual at the beach. Here’s how I used scientific practices and data collection to help me solve the Mystery of Ocean Beach.

2. Data Collection
Quantitative Data are anything that involves numbers. For example: percents, ratios, measurements, quantities, etc.
“The tree has 2000 leaves.”
Qualitative Data describe, but do not measure. For example: descriptions, comparisons, properties, patterns.
“The tree has broad, green leaves.”

3. Here are some of my data…
The objects were round and puffy. Many of them had sand stuck to them. They did not move or appear to be alive. Some of them were smashed. They covered the beach. Some were in the parking lot.
The first ones that I found were about 2 inches long, but then I found some that were only ¼ inch long. About 90% of them were white, but 10% were pinkish and star shaped.

4. What did Ms. Frank find at Ocean Beach?
Use the data I’ve given you to formulate a reasonable explanation to the question:
“What did Ms. Frank find at the beach?”

5. I collected a sample and took a picture.

6. Another Mystery! How did so many marshmallows end up on one beach?
How did the marshmallows get there?

7. Let’s formulate a Hypothesis!
A Hypothesis is a fancy Greek word for an educated guess.
Based on the data I’ve already given you and what you know about marshmallows, how do you think the marshmallows got on the beach?

8. ??????????????????????
Do you need more data?
What kinds of data would help?
How can you get the data you need?
What would Einstein do?

9. Let’s Estimate!

10. Taking a Sample
I don’t want to count every single marshmallow. That would take too long.
I could count the marshmallows in 1 square meter of the beach.
Then I can multiply that number by the area of the beach.
Will that give me a reasonable estimate?

11. Oh, come on, you learned area in 4th grade
Oh, come on, you learned area in 4th grade! Time to use those math skills.

12. Time to think like a scientist!
Are there variables that could affect the number of marshmallows in the square meter where I took my sample?

13. What’s a Variable?
A variable is something in an experiment that can be changed and affect the outcome.
Could seagulls have eaten some marshmallows?
Could people have picked some up?
Could some have washed out into the ocean?
Are my data reliable and accurate?
Do I need to take more samples to be sure?

14. More Qualitative Data…
Location: Ocean Beach is near San Diego, California
Date: July 5, 2012
I found some burned firecrackers near some of the marshmallows.

15. My Theory
A theory is a scientific explanation for an event or phenomenon based on reliable data that have been tested.
I think there was marshmallow fight at Ocean Beach on July 4th after the fireworks and it involved most of the town. I think this because there were many marshmallows scattered over a wide area.

16. What do you think?

17. I did some research online…
Ocean Beach Marshmallow Fight Involved 600+ Pounds of Ammo
By Gail Powell, July 5, 2011
By ten in the morning on July 5, an estimated 600 pounds of marshmallows had been picked up from the sands of Ocean Beach.
The annual marshmallow fight (which follows the Fourth of July fireworks) has become such a sticky mess that environmental organizations have to solicit volunteers to show up the next morning to clean up.
At 8:00 a.m., my son and I were greeted by what seemed like millions of marshmallows baking in the sand. With about 100 other Coastkeeper volunteers, we went — bag and grabber in hand — starting near the pier and walking north.
A City of San Diego lifeguard passing by on patrol thanked us and said, "The marshmallows are in the sand all the way up to Lifeguard Tower Three in north O.B.

18. And I found a video….. Ocean Beach Mystery
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