How to teach the times tables with a chart
A chart is a reference, not a drill. Students who stare at 144 squares learn little; students who are shown where the patterns live learn quickly. A 12 × 12 chart has 144 squares but only 78 different facts, because 7 × 8 and 8 × 7 are the same fact. A 10 × 10 chart has 55. Folding the chart on the board makes that visible, and it is often the first moment the tables feel small enough to learn.
A sensible order
- The 1s, 2s (doubles), 5s and 10s. Most students know these already; the chart shows them how many facts they have for free.
- The squares along the diagonal (1, 4, 9, 16, 25 …). Colour by Square numbers to find them.
- The 3s and 4s, with 4s as double the 2s twice over.
- The 9s, using the digit pattern below.
- The last few: 6 × 7, 6 × 8, 7 × 8 and 7 × 7. Only a handful remain, and “5, 6, 7, 8” helps: 56 = 7 × 8.
Get a fact from facts you know
Break it apart draws the strategies students are asked to explain in 3rd grade. Split a factor at 5 (7 × 8 is 5 × 8 and 2 × 8), take one group away from ten (9 × 6 is 10 × 6 take away one 6), double a fact (4 × 7 is double 2 × 7), or add one group to a square (6 × 7 is 6 × 6 and one more 6). Each split appears on the chart as two outlined rectangles, so the area model and the sentence match.
Patterns worth noticing
These are the twelve pattern cards in the tool. Each claim is checked by computation in our tests.
- The nines. The digits always add to 9 (18 → 1 + 8). The tens digit goes up by one while the ones digit goes down by one, because adding 9 is adding 10 and taking away 1.
- The fives take turns. They end in 5, 0, 5, 0, taking turns. An odd number of fives ends in 5 and an even number ends in 0, because two fives make a ten.
- Squares on the diagonal. They are the square numbers: 1 × 1, 2 × 2, 3 × 3 and on. The gaps between them are the odd numbers 3, 5, 7, 9, because the next square adds a row, a column and one corner.
- Odd times odd. An answer is odd only when both numbers are odd; even times anything is even. On the 1 to 12 chart that is 36 of the 144 squares: one in four.
- Digit sums in the threes. Every multiple of 3 has a digit sum that is also a multiple of 3 (51 → 5 + 1 = 6), and no other number does. It works because 10 is one more than 9.
- The elevens. 11 × 1 to 11 × 9 repeat the digit: 11, 22 … 99, because 11 is ten and one more. After that the pattern changes: 110, 121, 132.
- Six times an even number. Six times an even number ends in that number's last digit: 6 × 4 = 24, 6 × 8 = 48. The difference is 5 times an even number, which is always a whole number of tens.
- The eights count down. The last digits go 8, 6, 4, 2, 0 and start again, down by two each time, because adding 8 is adding 10 and taking away 2.
- The threes and sevens are mirror tunes. It is the same list: 3, 6, 9, 2, 5, 8, 1, 4, 7, 0. Two tables that add to 10 mirror each other in their last digits, because a × k and (10 − a) × (10 − k) always end in the same digit. Turn on Sound and play the two rows to hear it.
- Fold the chart. Every fact lands on its turn-around twin: 7 × 8 on 8 × 7. Only the 12 squares on the diagonal have no twin, so there are 78 different facts, not 144.
- Where does 24 live?. 24 lives in six squares on the 1 to 12 chart (2 × 12, 3 × 8, 4 × 6 and their twins). 36 lives in five, because 6 × 6 is its own twin. Only square numbers turn up an odd number of times.
- Next door to a square. The numbers either side of a square always multiply to one less than the square: 6 × 8 = 48 and 7 × 7 = 49. It is a handy way to remember 6 × 8.
Common mistakes to watch for
Students often read across the wrong row, or add instead of multiply. Hide the answers and ask them to say the equation aloud first. Skip counting is a bridge, not a goal: once a student can count by 6 to 42 they should start moving to recall, a few facts a week. Our facts helps here: tick only the facts the class can say in about three seconds, and spend the week's practice on the squares that are still blank.