Skip Counting (4s, 8s, 50s, 100s)

Activities to try

1. 1

   The doubling chain: stacked number lines for 2s, 4s and 8s

   Why it works: 8s are doubled 4s and 4s are doubled 2s; a slip in one count can be repaired using the other, because the step sizes nest inside each other.

   1. Lay out (or display) three aligned number lines starting at 0: one marked in 2s, one in 4s, one in 8s, with the same spacing so matching numbers sit directly above one another.
   2. Step along the 8s line one jump at a time. For each 8-jump, mark the two 4-jumps directly beneath it, and the four 2-jumps beneath those.
   3. Say aloud as you go: 'one jump of 8 is the same distance as two jumps of 4, which is four jumps of 2.'
   4. Count the 4s aloud (0, 4, 8, 12, 16…) and ring every other number starting from 0 — notice the circled numbers are exactly the 8s count (0, 8, 16…).
   5. Count backwards in 8s from 96, checking each step against the 4s line.
2. 2

   From skip count to equal groups and arrays

   Why it works: A skip count is repeated addition of equal groups; knowing the count lets you say how many groups make a total, which is exactly the multiplication fact.

   1. Build groups of four with counters: one group, two groups, three groups, saying the running total (4, 8, 12) and the matching fact ('three fours = 12').
   2. Arrange the same counters into an array (rows of four) so each skip-count step adds one row.
   3. Match skip-count totals to equal-groups statements, e.g. pair 'three groups of 8' with 24, 'five fours' with 20.
   4. Answer group-count challenges in both directions: 'How many fours in 20?' (five) and 'What is four groups of eight?' (32).
   5. Repeat the build for groups of eight, noticing each group of eight is two groups of four.
3. 3

   Counting in 50s and 100s with money and the hundred square

   Why it works: Counting in 50s can be understood as pairing up to hundreds (two 50s make 100); it also matches the 5s count with each number ten times bigger (5, 10, 15 → 50, 100, 150), but the pairing view carries the meaning. Boundary crossings require the hundreds digit to roll, and shading/marking makes each count's pattern visible.

   1. Pair up 50p coins (or £50 notes) to make pounds/hundreds: two 50s make 100, so count 50, 100, 150, 200… pairing as you go.
   2. Count on in 50s from 0 to 1000, deliberately slowing at each hundred boundary (…, 450, 500, 550; …, 950, 1000) and checking the hundreds digit rolls correctly.
   3. On a 1–100 hundred square, shade the 4s and 8s to see their column/diagonal patterns; then on a number line or track to 1000, mark the 50s and 100s to see them step evenly, with 50s landing twice as often as 100s.
   4. Count in 100s from 0 to 1000 and compare with the 50s on the same number line.
   5. State explicitly: 'how many 50s make 1000?' and check by pairing (two 50s = 100, so twenty 50s = 1000).