Smelly hands investigation

Today we followed the process of a scientific investigation and explored different ways to get rid of fish smell from hands. 10 students got fish smell all over their hands and then each one tried a different product to get rid of the smell. We then had some 'smellers' who went through and voted for the most effective product.

Here are the results:

1. No product - control (no votes)
2. Lemon Juice (9 votes)
3. Block of soap (13 votes)
4. Vinegar (4 votes)
5. Watery detergent (8 votes)
6. Toothpaste (10 votes)
7. Salt (no votes)
8. Baking soda (2 votes)
9. Water (no votes)
10. Stainless steel (1 vote)

We then had a discussion around the variables and the quality of the experiment. We realised that there was lots of variables that made the experiment not very accurate and reliable. These included:

• The amount of fish smell on each set of hands could have been different.
• The fish could have being contaminated by previous hands leaving oils, etc.
• Peoples hands could react differently to the smell and the products.
• How well each person washed with the product and then rinsed clean.
• Peoples ability to smell or how 'controlled' their smelling was.

We then discussed how this experiment could have been improved. Here are some of the ideas:

• Use an eye dropper and put the same amount of fish oil on each hand.
• Wash all hands before the test.
• Increase the sample size of the testers and the smellers.