Computer Skills

Beginner

60 mins

Teacher/Student led

+80 XP

What you need:
Chromebook/Laptop/PC or iPad/Tablet

More Formulas: MIN, MAX, COUNT

Learn to use MIN, MAX, COUNT and COUNTA functions to find the smallest and largest values in your data and count how many items you have. Apply these formulas to answer real questions about your project budget.

Warning: Your screen size is quite small for viewing this. Rotate your device into landscape mode if you can.

1 Introduction
2 Key Concepts
3 Step-by-step Task
4 Common Issues
5 Independent Practice
6 Reflection
7 Lesson Summary
Quiz

1 - Introduction

Welcome

Last time you used SUM and AVERAGE to total and average the numbers in your project budget. Today you'll add four more formulas that answer a different kind of question: what is the smallest number, what is the biggest, and how many values are actually there? These are the functions that turn a raw list of costs into real information you can use.

By the end of this lesson, you will be able to:

Use =MIN, =MAX, =COUNT and =COUNTA on a range of cells
Choose COUNT (numbers only) versus COUNTA (any non-empty cell) for the right job
Answer real questions about your data by picking the right function

Warm-up

Imagine you're helping to plan a class fundraiser. Someone hands you a list of 40 items and their prices and asks three quick questions. What is the cheapest item? What is the most expensive? How many items are on the list? Could you answer any of those using just SUM and AVERAGE? Which would be easy to spot by eye, and which would you hate to work out by hand from 40 rows?

Teacher Notes

Link the warm-up straight back to last lesson's SUM/AVERAGE work. Students should realise quickly that SUM and AVERAGE cannot answer min/max/count questions at all.

👇 Mark your steps as done as you complete them.

+5 XP

2 - Key Concepts

Four new functions today. They all work on a range of cells and they all take the same shape: =FUNCTION(range). The trick is knowing which one to reach for.

Concept	Why it matters	Example
MIN — returns the smallest number in a range	Finds the cheapest item instantly.	`=MIN(B2:B20)` on a shopping list returns the lowest price.
MAX — returns the largest number in a range	Finds the most expensive item at a glance.	`=MAX(B2:B20)` on a party shopping list shows the priciest thing.
COUNT — counts cells that contain numbers only, ignoring text	Tells you how many rows actually have a price filled in.	`=COUNT(B2:B20)` on a class-trip cost list returns 18 if two rows are missing a price.
COUNTA — counts all non-empty cells, text and numbers together	Tells you how many items are on the list overall, even when the cells hold words.	`=COUNTA(A2:A20)` on a class-trip sign-up sheet counts every student's name.

Choosing COUNT vs COUNTA — the 10-second test

Look at the column you want to count. If its cells hold numbers (prices, quantities), use =COUNT. If its cells hold words (item names, names of people), use =COUNTA. Running =COUNT on a column of words returns 0. That is the single most common mistake at this stage. When in doubt, COUNTA is the safer choice because it counts both.

Teacher Notes

The COUNT vs COUNTA distinction is the one thing students usually get wrong. Flag the 10-second test and come back to it during the portfolio build.

👇 Mark your steps as done as you complete them.

+10 XP

3 - Step-by-step Task

You'll build a short worked example together: a six-item cost list for a class fundraiser, then answer five questions about it using MIN, MAX, COUNT, and COUNTA. This is practice, not portfolio work, so you don't need to save the file.

Teacher Notes

Students work through a shared worked example first so the portfolio build that follows is just repeating the pattern with their own data.

+15 XP

4 - Common Issues

Common Issues

If something looks wrong on your sheet, check the table below before starting the portfolio build. Most problems are caused by picking the wrong function or the wrong range.

Issue	Solution
`=COUNT` returns 0 on a column of item names	COUNT ignores text. Switch to `=COUNTA` if the column holds words, not numbers.
`=MIN` returns 0 instead of my smallest price	There is probably an empty cell or a literal 0 in the range. Check each cell; empty cells are ignored, but a cell showing 0 will win.
`#NAME?` or `#VALUE!` error appears	Usually a typo in the function name (`=MIMN(...)`), or a missing bracket. Click the cell and rewrite the formula slowly.
The answer looks right but updates to the wrong number when I change a cost	Your range is too short or too long. Click the cell, read the range in the formula bar, and make sure it covers every row of data and nothing else.

Quick check: which function would you use?

Before you start your own sheet, match each question to the right function in your head. No need to write anything down.

Question	Function?
What is the shortest time anyone ran the 100m?	?
How many people have signed up on a list of names?	?
What is the top score out of 12 test results?	?
How many prices are actually filled in (so I can spot missing ones)?	?

Answers: MIN, COUNTA (names are text), MAX, COUNT.

Teacher Notes

The COUNT-returning-0-on-text issue is the most common. The quick check gives you a pulse on whether students have internalised the COUNT vs COUNTA rule before they open their own budget. Ask the class to call out answers chorus-style.

+10 XP

5 - Independent Practice

Independent Practice

Your goal: Use MIN, MAX, and the right count function on your own project budget, so the sheet tells you at a glance which item is cheapest, which is most expensive, and how many items are on the list.

Time: ~15 minutes

Task: Open {{code:05_project_budget}} from your {{code:Digital_Portfolio}} folder. Below your existing SUM and AVERAGE rows, add three clearly labelled summary cells: MIN Cost, MAX Cost, and Item Count. For Item Count, use the 10-second test from the key concepts to decide whether COUNT or COUNTA is correct. Twist: Once your three formulas work, temporarily delete one of the prices from your cost list. Watch what happens to MIN, MAX and your Item Count. Does the count drop? Would it have dropped if you had picked the other count function? Put the price back when you're done.

Success criteria:

Three new summary cells appear under your cost list, each with a clear label beside the value
Each value updates automatically when you change a number in your cost list — try it and check
Your Item Count returns the real number of items on the list (not 0), and you can say why you picked COUNT or COUNTA
You can describe what happened to MIN, MAX and the count when you deleted a price, and whether your count function noticed

Teacher Notes

Circulate and ask each student which function they used for Item Count and why. The delete-a-price twist is designed to surface the COUNT vs COUNTA difference in practice — if a student used COUNT, deleting a price drops the count from (say) 6 to 5; if they used COUNTA on the item-name column, the count stays at 6 because the name is still there. Either outcome is a good teaching moment.

+15 XP

Unlock the Full Learning Experience

Get ready to embark on an incredible learning journey! Get access to this lesson and hundreds more on our learning platform.

Get started

Copyright Notice
This lesson is copyright of Coding Ireland 2017 - 2025. Unauthorised use, copying or distribution is not allowed.

More Formulas: MIN, MAX, COUNT

Teacher Class Feed

1 - Introduction

Welcome

By the end of this lesson, you will be able to:

Warm-up

2 - Key Concepts

Choosing COUNT vs COUNTA — the 10-second test

3 - Step-by-step Task

4 - Common Issues

Common Issues

Quick check: which function would you use?

5 - Independent Practice

Independent Practice

Unlock the Full Learning Experience

XP