🪘 Drum size and sound: the whole packet

🪘 Drum size and sound · 3rd–7th grade · 1 day of testing · free · 45 minutes a sitting

My days, if the fair is 14 days away

Count back from your fair day and write in each date. Fewer days than this? The jobs share days, in this order; nothing is skipped.

Dates from my teacher

• My question is due
• Testing starts
• My results table and graph are due
• My board is due

In this packet

1. 🗓️ My project plan
2. 💭 My hypothesis
3. 🧺 Change, measure, keep the same
4. 🪜 My steps
5. 📊 My results
6. 📓 My logbook
7. ✅ My conclusion
8. ✂️ Board titles to cut out
9. 🏅 The judge's questions and my certificate

If I change how big the drum is, then how far away the banged tray can be and still make the salt jump will ________________, because _____________________________________________

What I think will happen, in my own words:

3 levels × 3 tries at each = 9 tries in all. If anything you keep the same changes, you won't know which change made the difference.

What I need

• 🥤 Paper cups: 1
• 🫙 A clear jar or tall glass: 1
• 🥣 A big bowl: 1 big one
• 🎞️ Clear plastic wrap
• ➰ Rubber bands: 3
• 🧂 Salt: a pinch for each drum
• 🍽️ A baking tray or big plate: a metal baking tray
• 🥄 A spoon: a wooden spoon
• 📏 A tape measure, or a long ruler

Be safe: 🧽 A bit messy

1. Stretch plastic wrap tight over the cup, the jar and the bowl, each with a rubber band.
2. Tap each skin with a finger: they should all feel just as tight.
3. Sprinkle a pinch of salt in the middle of the cup drum.
4. Bang the tray once beside the drum. Never bang it next to anyone's ears.
5. Step back 20 cm at a time, banging once each time, until the salt stops jumping.
6. Measure how far the tray was at the last bang that made the salt jump.
7. Do it two more times with the cup, then three times each with the jar and the bowl.
8. Draw a bar for each drum. Which one felt the bang from farthest away?

Write each number in your results table the moment you measure it.

I changed: Drum   I measured: how far away the banged tray can be and still make the salt jump (cm)

MY GRAPH (a bar graph: drum along the bottom, cm up the side)

What I noticed: ______________________________________________

Write something every day you work on it, even the days you only gather things. More days? The three-page logbook prints from peabody.kids/science-fair/templates/logbook.

My hypothesis was ☐ right ☐ partly right ☐ not right.

I know because my numbers show:

What surprised me, or what might have gone wrong (7th and up):

Next time I would test:

Idea: Change a second thing: test each drum with the wrap tight and with it a little loose.

1. What made you want to ask this question? Say something like: I wanted to know: does a bigger drum feel sound from farther away?
2. What did you think would happen, and why? Say something like: I thought changing how big the drum is would change how far away the banged tray can be and still make the salt jump, and I wrote down why.
3. What did you change, and what did you measure? Say something like: I changed how big the drum is (Paper cup, Clear jar, Big bowl) and measured how far away the banged tray can be and still make the salt jump in cm.
4. What did you keep the same, and why does that matter? Say something like: I kept the same plastic wrap, pulled just as tight and the same pinch of salt the same, so only how big the drum is was different.
5. How many times did you test it? Say something like: 3 times at each of my 3 levels, and I found the middle number.
6. What did you find out? Show me in your numbers. Say something like: Look at my table: Paper cup and Big bowl gave different numbers, and here's the pattern.
7. Was your hypothesis right? How do you know? Say something like: My numbers show whether I was right, partly right or not, and I can show you where.
8. Did anything go wrong, or surprise you? Say something like: One try was odd, so I did it again and wrote it in my logbook.
9. If you did it again, what would you change or test next? Say something like: I'd change a second thing: test each drum with the wrap tight and with it a little loose.