🖊️ Hidden colours in marker ink: the whole packet

🖊️ Hidden colours in marker ink · 2nd–6th grade · 1 day of testing · about $2 · 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 the colour of the marker, then how many bands of colour show on the strip will ________________, because _____________________________________________

What I think will happen, in my own words:

4 levels × 3 tries at each = 12 tries in all. If anything you keep the same changes, you won't know which change made the difference.

What I need

• 🖊️ Washable markers: black, brown, green and purple: one of each colour
• ⚪ Round paper coffee filters: 3
• 🚰 Water from the tap
• 🫙 A clear jar or tall glass: a wide glass
• ✏️ A pencil
• ⏱️ A stopwatch or a kitchen timer
• ✂️ Kid scissors
• 📏 A ruler
• 🩹 Tape

Be safe: 💧 Water

1. Cut twelve strips, 1 cm wide and 10 cm long, from flat coffee filters.
2. Draw a pencil line 2 cm up from the bottom of each strip.
3. Make a fat dot of marker on each line: three strips each of black, brown, green and purple.
4. Write the marker colour at the top of each strip in pencil.
5. Pour 1 cm of water into a wide glass.
6. Tape four strips, one of each colour, to a pencil laid across the glass.
7. Slide the strips so their bottoms touch the water and the dots stay dry above it.
8. Wait until the water has climbed near the top. That takes about fifteen minutes.
9. Lift the strips out, lay them flat, and count the bands of colour on each strip.
10. Write each count in your table, then do it two more times with new strips.
11. Find the mean for each marker, and draw a bar graph.

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

I changed: Marker   I measured: how many bands of colour show on the strip (bands of colour)

MY GRAPH (a bar graph: marker along the bottom, bands of colour 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: use a washable marker and a permanent marker of the same colour, and graph the bands for each.

1. What made you want to ask this question? Say something like: I wanted to know: how many colours hide in a marker's ink?
2. What did you think would happen, and why? Say something like: I thought changing the colour of the marker would change how many bands of colour show on the strip, and I wrote down why.
3. What did you change, and what did you measure? Say something like: I changed the colour of the marker (Black, Brown, Green, Purple) and measured how many bands of colour show on the strip in bands of colour.
4. What did you keep the same, and why does that matter? Say something like: I kept strips cut from the same kind of coffee filter and the same size of dot the same, so only the colour of the marker was different.
5. How many times did you test it? Say something like: 3 times at each of my 4 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: Black and Purple 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: use a washable marker and a permanent marker of the same colour, and graph the bands for each.