See the idea. Put it to the test.

Find a practical

1. Technologies K–10 · Years 1–2

   A yes/no sorting machine: branching with attribute shapes

   A branch is a question with two answers that sends each item down a different path, so two yes/no questions in a row sort 12 shapes into 4 groups.

   Practical, model not builtLow risk

2. Technologies K–10 · Years 1–2

   Repeat loops in a bead bracelet

   A repeat instruction (iteration) makes a short list of steps produce a long pattern, so 'repeat 5 times: red, red, blue' threads 15 beads.

   Practical, model not builtLow risk

3. Technologies K–10 · Years 3–4

   A Scratch maze game: keyboard input and wall checks

   A visual program uses input (arrow keys), branching (if touching the wall colour) and repetition to control a sprite, and a test table shows whether every rule works.

   PracticalLow risk

4. Technologies K–10 · Years 3–4

   Higher or lower: finding a number from 1 to 100 in 7 guesses

   Comparing each guess with the secret number (higher or lower) and always guessing the middle of what is left halves the search each time, so any number from 1 to 100 is found in at most 7 guesses.

   Practical, model not builtLow risk

5. Technologies K–10 · Years 5–6

   A micro:bit light meter calibrated against a lux meter

   A sensor turns light into a number on its own scale (0 to 255 on a micro:bit), and a calibration table made against a lux meter turns those numbers into a judgement such as 'too dark to read'.

   Practical, model not builtLow risk

6. Technologies K–10 · Years 5–6

   micro:bit rock, paper, scissors: random numbers, variables and branching

   A visual program stores a random number in a variable and branches on it to show rock, paper or scissors, and counting 60 results tests whether each branch comes up about a third of the time.

   Practical, model not builtLow risk

7. Technologies K–10 · Years 5–6

   Sorting with a balance scale: counting comparisons

   Different sorting algorithms put the same 8 containers in order but need different numbers of comparisons, so an algorithm can be judged by how many steps it takes.

   Practical, model not builtLow risk

8. Technologies K–10 · Years 7–8

   Python functions tested against known values

   A function packages a calculation so it can be tested against known values, and testing floating-point results needs a tolerance because decimals are stored in binary.

   Practical, model not builtLow risk

9. Technologies K–10 · Years 7–8

   Soldering an LED indicator on stripboard

   A soldered joint makes a permanent electrical connection, and choosing the resistor from the LED's datasheet keeps the current safe: I = (9.0 V − 1.9 V) ÷ 680 Ω = 10.4 mA.

   PracticalMedium risk

10. Technologies K–10 · Years 7–8

    Tracing nested loops by hand before running them

    A trace table follows every variable through each pass of a loop, so the output of nested loops can be predicted, and errors such as an off-by-one range found, before the program runs.

    Practical, model not builtLow risk

11. Technologies K–10 · Years 9–10

    Bubble sort against merge sort: counting comparisons as lists grow

    Bubble sort compares every pair of neighbours on every pass and needs about n²/2 comparisons, while merge sort needs about n log2 n, so the gap between them grows quickly with list size.

    Practical, model not builtLow risk

12. Technologies K–10 · Years 9–10

    Linear and binary search: counting comparisons on a million items

    Linear search checks items one by one, while binary search halves a sorted list each step, so for a million items the worst case falls from a million comparisons to 20.

    Practical, model not builtLow risk

13. Technologies K–10 · Years 9–10

    Logic gates from switches: AND, OR, NOT and the two-way light

    Switches in series behave as AND, switches in parallel as OR, a push-to-break switch as NOT, and two two-way switches as the staircase light, so logical operators in algorithms have physical circuits behind them.

    Practical, model not builtLow risk

14. Technologies K–10 · Years 9–10

    Testing a leap-year function with boundary cases

    A program is validated by comparing its output with expected results for a planned set of test cases, and boundary cases catch errors that everyday cases miss.

    Practical, model not builtLow risk