Column Tower — Lesson 77: The tall tower: up to ten numbers
Mixed column practice →Lesson 77: Abacus long column sums: ten numbers
Level 6, Column Tower. A tall column of one-digit numbers. The sheet keeps your place; the beads keep the answer.
What your child does, card by card
The tall tower: up to ten numbers. Ten lines without losing your place. PlayType opens the lesson: “Ten numbers tall. Stay calm, one line at a time.”
Six lines: the abacus makes 5, 8, 5, 15, 10, 11, 17, 7 and 9 by itself, a green ring on each bead just before it moves, and the sum sheet below ticks each line. Stay calm. One line at a time.
In Try it a green ring marks the next bead while your child works out the column 5 + 3 + 7 - 4 + 6 + 2 - 8 + 9 + 4 - 6.
The tiny practice drops the ring: work out the column 8 - 3 + 6 + 5 - 7 + 9 - 2 + 4, each round starting from its own number.
In your head: the abacus is covered and your child works out 1 + 2 + 3 + 4, 9 - 1 - 2 - 3 and 5 + 5 + 5 - 5, picking each answer from 3, 10 and 12.
You're ready! Ten lines tall, one at a time.
What this lesson trains
19 answers, roughly five minutes: 29 moves of the beads, 7 of them with the top bead and 22 with bottom beads. Up to 24, read and set from the left. Then 3 quick looks in your head. The friend rules here: +7 = −3 +10, −4 = −5 +1, +9 = −1 +10, −6 = −10 +5 −1, +6 = +1 −5 +10, −7 = −10 +3 and +4 = −6 +10, used in 8 of 16 sums.
Your child’s first moves: work out the column 5 + 3 + 7 - 4 + 6 + 2 - 8 + 9 + 4 - 6.
The sum sheet
Below the abacus a sum sheet replaces the hands: it writes the column out, lights the line your child is on and ticks each line done; the total appears after the last line. The beads hold the running total the whole way down.
What PlayBuddy and PlayType say
PlayType: “Ten numbers tall. Stay calm, one line at a time.”
PlayBuddy: “One line at a time, top to bottom.”
Stars
Three stars for up to 1 slip in 19 answers, two stars for up to 4.