Presentation: Organising and Sharing Microscope Images of Cells

Slide 1 of 7 · Settling starter · Science · Year 9

4 minutes

A folder in a mess: the Year 9 microscope photos

Class 9C at Ysgol Cwm Dyfnant photographed cells under the microscope. The photos sit in one badly named folder on one laptop. Mrs Elen Morgan, Head of Science, wants them on the school’s Hwb cloud storage so every Year 9 pupil can revise from them.

While the register is called: write your name, class and date on your worksheet, then read sections 1 and 2 of the stimulus sheet with your partner.

Starter question: Where are the photos kept right now, and why does Mrs Morgan say that is a risk?

DCF: Interacting and collaborating → Storing and sharing No computers or microscopes needed · calculator ready

Supply teacher script (no subject knowledge needed)

Hand out: one worksheet per pupil and one stimulus sheet (The Year 9 microscope photos: a folder in a mess) between two. Every pupil needs a pen and a calculator. All measurements are printed as numbers, so nobody needs a ruler. The school, staff, pupils and folder are invented; the typical cell sizes on the fact card are real.

Say aloud: “Write your name, class and date at the top of your worksheet. While I take the register, read sections 1 and 2 of the stimulus sheet with your partner, the message from Mrs Morgan and the folder as it is now, and answer the starter question in rough.”

Starter answer: All the photos are in one folder called Y9 microscope stuff, which is only on the prep room laptop. If the laptop breaks, everything is lost, and nobody can tell from the names what most photos show.

Slide 2 of 7 · Today’s brief and key words · Science · Year 9

2 minutes

Your brief: work out the real cell sizes, then sort out the folder

You will calculate the magnification of each photo and the real size of the cells, then design a naming rule, rename all 10 files, draw a folder tree, set sharing permissions and plan a 3-2-1 back-up. Show every piece of working.

Total magnification

Eyepiece × objective. Every eyepiece in the lab is ×10, so a ×4 objective gives ×40.

Micrometre (µm)

1 mm = 1000 µm. To change mm to µm, multiply by 1000.

Version number

v01, v02 and so on. Numbers only go up, so v02 is always newer than v01.

3-2-1 back-up

3 copies, on 2 different types of storage, with 1 copy off-site, for example the cloud.

LNF: Numeracy → Learning about geometry helps us understand shape, space and position, and learning about measurement helps us quantify in the real world → Measurement Working out, not just answers

Slide 3 of 7 · Steps 1 and 2: magnification and real sizes · Science · Year 9

16 minutes

Step 1 & Step 2: how big are the cells really?

Step 1 (8 min): use the lab notes (section 3) and the fact card (section 4). Complete the total magnification for photos A, C, E, F and J, then find photo G’s missing objective lens in (b).

Step 2 (8 min): actual size = image size ÷ magnification. Answer in mm, then convert to µm, then check each size is sensible against the fact card. Answer (f) and (g).

File	Eyepiece	Objective	Total magnification
A	×10	×10	10 × 10 = ×100

Model for Step 2(a): onion cell, photo A: 25 ÷ 100 = 0.25 mm; 0.25 × 1000 = 250 µm. Sensible? Yes, inside 200 to 300 µm.

Steps 1 and 2 on your worksheet · 16 minutes Image size and actual size must be in the same unit

Supply teacher script (no subject knowledge needed)

Say aloud: “The first row of Step 1 and the first row of Step 2 are on the board. Multiply eyepiece by objective for each photo, then divide the image measurement by the magnification to get the real size in mm, and multiply by 1000 for micrometres. Write the multiplication or division every time. Calculators out.”

Quick check, Step 1: A ×100, C ×400, E ×400, F ×400, J ×100. (b) 10 mm ÷ 0.25 mm = ×40, so the objective was 40 ÷ 10 = ×4, the lowest power lens.

Quick check, Step 2: (b) cheek cell 24 ÷ 400 = 0.06 mm = 60 µm; (c) onion nucleus 6 ÷ 400 = 0.015 mm = 15 µm; (d) pondweed cell 40 ÷ 400 = 0.1 mm = 100 µm; (e) chloroplast 2 ÷ 400 = 0.005 mm = 5 µm. All sensible against the fact card. (f) 0.06 is correct but in mm; they wrote µm without multiplying by 1000, and the fact card says a cheek cell is about 60 µm, 1000 times bigger. (g) 0.25 mm × 400 = 100 mm; the photo is only 80 mm wide, so a whole cell would not fit.

Slide 4 of 7 · Steps 3 and 4: name the files · Science · Year 9

14 minutes

Step 3 & Step 4: design a naming rule, then rename all 10 files

Step 3 (5 min): every file name must record the sample, the magnification (written as x100, never the × sign), the date taken as YYYY-MM-DD and the group, plus a version number. Write your pattern, one example, 2 more rules, and answer (c).

Step 4 (9 min): decide whether each file A to J is kept or removed. Kept files get a new name using your rule; removed files get a reason.

Model pattern: sample_magnification_YYYY-MM-DD_group_version.jpg

File	Keep or remove?	New name, or the reason for removing it
A	Keep	onion-epidermis_x100_2026-09-15_G2_v01.jpg

DCF: Interacting and collaborating → Storing and sharing Same rule for every kept file · no pupil names

Supply teacher script (no subject knowledge needed)

Say aloud: “A model pattern and the first row of the Step 4 table are on the board. Your order can be different, but it must record all 4 things and a version number, and you must use it the same way for every file you keep. Photo G’s magnification is the one you worked out in Step 1(b).”

Quick check, Step 3: accept any pattern with sample, magnification, YYYY-MM-DD date and group plus a version number. (b) model rules: no spaces and all lower case (hyphens inside a part, underscores between parts); never a pupil’s name, use the group number; the date is the date taken, even for an edited version. (c) A computer sorts character by character from the left, so 2026-09-15 puts year, then month, then day, and files sort into date order; with 15-09-2026 every photo taken on the 15th of any month would sort together.

Quick check, Step 4: keep A, C, D, E, F, G and J; remove B (exact duplicate of A), H (completely out of focus) and I (shows 4 pupils’ faces, no science). Model names: C cheek-cells_x400_2026-09-15_G1_v01.jpg; D cheek-cells_x400_2026-09-15_G1_v02.jpg (the labelled version of C); E onion-epidermis_x400_2026-09-15_G3_v01.jpg; F pondweed-leaf_x400_2026-09-16_G4_v01.jpg; G onion-epidermis_x40_2026-09-16_G2_v01.jpg; J cheek-cells_x100_2026-09-15_G3_v01.jpg, with Dafydd’s name removed.

Slide 5 of 7 · Steps 5, 6 and 7: folders, sharing and back-up · Science · Year 9

18 minutes

Step 5, Step 6 & Step 7: folders, who can do what, storage and back-up

Step 5 (5 min): draw a folder tree no more than 4 levels deep, originals apart from edited versions, and write which new file names go where. Answer (b) on “final final.jpg” and write one rule that stops an original being overwritten.

Step 6 (5 min): no access, view or edit for Year 9 pupils, science teachers and anyone with the link, each with a reason, then one check before any image is shared.

Step 7 (8 min): 1 kB = 1000 bytes, 1 MB = 1000 kB, 1 GB = 1000 MB. Answer (a) to (c) with working, then plan a 3-2-1 back-up in (d).

Who	No access, view or edit?	Reason
Year 9 pupils	View, through their Hwb account	They open and download photos for revision but must not delete or change them for everyone else.

Steps 5, 6 and 7 on your worksheet · 18 minutes Divide by 1000 at each step and label the unit

Supply teacher script (no subject knowledge needed)

Say aloud: “Three steps in 18 minutes. Step 5 is the folder tree and a version rule, Step 6 is the sharing table, with the first row on the board, and Step 7 is the storage sums and the back-up table. The fact card gives you every number you need: 12 megapixels, 3 bytes per pixel, 3.6 MB per JPEG, 2 GB allowance, 8 classes, 4 groups, 5 photos each.”

Quick check, Steps 5 and 6: model tree: Science → Year 9 cells microscope images → 01 Originals (never edited) with animal-cells (C, J) and plant-cells (A, E, F, G), 02 Labelled versions (D), 03 Admin. (b) “Final final” says nothing about what changed or when and the next edit becomes “final final final”; numbers only go up. Rule: never edit a v01 file, save every change as a new file with the next version number, and give teachers alone edit access to Originals. Step 6: science teachers edit (they add, rename and remove photos each year); anyone with the link no access (a forwarded link could reach anyone, school accounts only). Check: open every image before uploading and make sure no face, name or personal detail appears in the picture or the file name.

Quick check, Step 7: (a) 12 000 000 × 3 = 36 000 000 bytes = 36 000 kB = 36 MB; 36 ÷ 3.6 = 10 times smaller. (b) C 3400 kB = 3.4 MB, D 3500 kB = 3.5 MB; kept files 3.6 + 3.4 + 3.5 + 3.8 + 3.7 + 3.5 + 3.3 = 24.8 MB. (c) 8 × 4 × 5 = 160 photos; 160 × 3.6 = 576 MB a year; 2000 ÷ 576 = 3.47, so 3 full years; uncompressed 160 × 36 = 5760 MB = 5.76 GB a year, so not even 1 year. (d) model: 1 Hwb cloud, cloud, off-site; 2 prep room laptop, laptop hard drive, on-site; 3 external hard drive locked in the prep room cupboard, removable hard drive, on-site. Accept any plan with 3 copies, 2 types and 1 off-site.

Slide 6 of 7 · Self and partner check · Science · Year 9

2 minutes

Check your work as if you were Mrs Morgan

Tick each success criterion you have met. Then correct 1 thing: the most common slip is a size written in µm without multiplying by 1000.

I can work out total magnification and use magnification = image size ÷ actual size, rearranged when needed, showing my working.
I can convert mm to µm and kB to MB to GB, and check whether an answer is sensible.
My naming rule records sample, magnification, date and group, and I used it the same way for every file I kept.
My folder tree keeps originals apart from edited versions, and my version rule means no original is ever overwritten.
My sharing permissions give each person only the access they need, and no shared image shows a pupil’s face or name.
My back-up plan follows 3-2-1, and my calculations show whether the storage allowance is big enough.

2 minutes · self check Finished early? Try the sorting puzzle at the bottom of your sheet

Slide 7 of 7 · Plenary review · Science · Year 9

2 minutes

Quick-check answers before handing in

Check these 3 answers before your worksheets are collected.

Question	Correct answer
What was the missing objective lens for photo G?	10 mm ÷ 0.25 mm = ×40 total, so the objective was ×4.
Which 3 files should be removed, and why?	B (duplicate of A), H (out of focus), I (pupils’ faces).
How many full years of JPEG photos fit in 2 GB?	576 MB a year, 2000 ÷ 576 = 3.47, so 3 full years.

Check your name and class are on your worksheet Leave stimulus sheets neat on the desk