Multiply by the ones, then by the tens. Add the two rows. A zero holds the ones place in the second row.
Worked example
Use the standard algorithm: 293 × 30 = ?
Answer:8790
Multiply by the ones: 293 × 0 = 0. Multiply by the tens (a zero holds the ones place): 293 × 30 = 8790. Add: 0 + 8790 = 8790. Answer: 8790.
For grown-ups: Standard multiplication algorithm. Below: three problems to try with the worked answers, and a free printable sheet. Children can practise the same skill as a game, with no sign-up and no ads.
CCSS 5.NBT.B.5
What this practises, for teachers
Practices standard multiplication algorithm (5.NBT.B.5). A printable sheet with its answer key, worked answers on the page, no accounts.