Create one continuous premium Grade 6 mathematics animation titled “The Sieve of Eratosthenes”. Integrate narration and visual directions in sequence. Use a large, perfectly aligned number grid from 1 to 100. Cross-outs and circles must remain readable; never cross out a prime number.
SEQUENCE 1 — START WITH 1
Visual: display grid 1–100. Cross out 1 in a distinct colour and label “1 is neither prime nor composite.”
Narration: “Start with the numbers from one to one hundred. First, cross out one. It is neither prime nor composite.”
SEQUENCE 2 — CIRCLE 2
Visual: circle 2 as the first prime. Cross out every other multiple of 2: 4, 6, 8, 10 and onward to 100. Keep 2 circled and untouched.
Narration: “The first uncrossed number is two. Circle it: two is prime. Now cross out the other multiples of two, because they have two as a factor.”
SEQUENCE 3 — NEXT UNCROSSED NUMBER
Visual: circle 3. Cross out multiples of 3 that are not already crossed out: 9, 15, 21, 27, and onward. Do not cross out 3.
Narration: “The next uncrossed number is three. Circle it. Cross out the multiples of three that are still uncrossed.”
SEQUENCE 4 — CONTINUE THE SIEVE
Visual: next uncrossed number 5: circle it and cross out remaining multiples of 5. Then circle 7 and cross out its remaining multiples. Continue the sieve correctly through the grid; only prime numbers remain circled. Show each new prime chosen as the next uncrossed number, without needing to narrate every crossed-out value.
Narration: “Continue with the next uncrossed number. Circle it, then cross out its multiples that remain. Repeat the process. The circled numbers are prime; the crossed-out numbers greater than one are composite.”
SEQUENCE 5 — REVEAL THE PRIMES
Visual: show the correctly completed sieve and highlight the primes up to 100:
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97.
Narration: “Here are the prime numbers up to one hundred. Each has exactly two factors: one and itself.”
SEQUENCE 6 — THINK AND CHECK
Visual: ask “Why is 91 crossed out?” Pause, then reveal 91 = 7 × 13. Ask “Why is 97 circled?” Reveal that no smaller prime number divides it exactly; keep explanation at Grade 6 level.
Narration: “Why is ninety-one crossed out? It is seven times thirteen, so it is composite. Ninety-seven remains circled because it has no factor other than one and itself.”
End memory card: “Sieve: circle the next uncrossed number; cross out its other multiples; repeat.” Do not teach prime factorisation.
