Every week we feature a fun and/or educational activity you can try at home or in the classroom. We have recently begun mailing our Gift Catalog for this year's holiday season and will be featuring activities, like how to make your own thermometer, that highlight the items available.
A new offering in this year's catalog is the Community Animal Health Worker Kit. In many countries, access to veterinary care is limited, so Heifer International trains individuals to become Community Animal Health Workers (CAHWs) and teaches them animal health, husbandry, breeding, nutrition and housing. This kit can include a thermometer, stethoscope, hoof trimmer, scalpels, gloves, disinfectants and even important medicine.
A basic piece of equipment a CAHW carries is a thermometer. For today's activity, you will learn how to make our own thermometer, and learn how they work.
Pour equal amounts of tap water and rubbing alcohol into the bottle, about 1/8 to 1/4 full. Add a couple of drops of food coloring, and mix. Put the straw in the bottle, making sure it doesn't touch the bottom. (Do not drink the mixture.) Seal the neck of the bottle and keep the straw in place with the modeling clay, so the straw stays in place.
Wrap your hands around the bottle and watch what happens. Just like a real thermometer, the mixture expands when warmed. This liquid no longer fits in the bottle, so it expands into and up the straw. If the bottle got very hot, the liquid would come up through the top of the straw.
Watch your thermometer throughout the day and see how the liquid changes. What happens if your thermometer is in shadow or in sunlight? What happens when it gets colder? How does wind affect the thermometer? Of course, you will need to a real thermometer that is carefully calibrated to get an accurate reading but this is a great way to see how it works.
For more details on this make your own thermometer activity and others, go to Energy Quest's website.
Read about Irene Pandosen, a CAHW and Heifer project participant in the Philippines.