Lesson 2: Zero on an abacus and how to clear it
Level 1, Bead Village. Today you learn to spot zero, and to clear the abacus.
What your child does, card by card
Zero: a clear abacus. Zero is a number too. PlayBuddy opens the lesson: “Zero is a number too. Let's find it!”
No bead on the bar: that is zero. We call it clear. A yellow line goes round the bar as the kids name it. 3 and 5 appear on the beads, then the rod clears again. Each label lights in turn: “On the bar: counts” and “Off the bar: zero”. After the show, the child can touch: “No bead on the bar: the little number says 0.”
Closed hands are zero: no finger up. No thumb out. The abacus makes 4, then clears. Here the hands lead: they show 4, 3, 2, 1, zero, 5 and zero, and a moment later the beads copy each one. The card ends on a touch: “Tap a finger to open it. Tap again to close it.”
Top bead up, bottom beads down, on a real abacus. Two moves clear the abacus. First the pointer finger turns yellow on a drawn hand while the abacus moves. After that your child must clear 8 and 4, guided by a green ring and the finger’s name. On a real abacus you can also tilt it and slide a finger along the bar.
In Try it a green ring marks the next bead while your child clears 3, 5 and 9.
The tiny practice drops the ring: clear 1, 4, 6 and 8, each round starting from its own number.
In your head: the abacus shows a number for 1.5 seconds, then hides under a cloud, and your child answers “Was it clear?” with Yes or No. The 4 rounds show 3, zero, 5 and zero.
You're ready! You can spot zero and clear the abacus.
What this lesson trains
13 answers in about five minutes. The tasks take 13 bead moves in all: 5 with a top bead and 8 with bottom beads. All 9 bead tasks end on zero. 9 is the top number here. Then 4 quick looks in your head.
Your child’s first moves: clear 8 and 4.
Fingers and hands
Below the abacus the drawn hands show zero and 1, 2, 3, 4, 5, 6, 8 and 9 here, finger for bead.
On “Closed hands are zero” the hands move first and the beads follow, so your child sees that a finger and a bead move together: open a finger and a bead goes to the bar, close it and the bead goes back.
Real fingers are a different thing from the finger abacus, so they get their own card: on a real soroban the pointer finger pulls bottom beads down and moves the top bead. We cannot see your child’s hand, so this is shown, never marked wrong; with a real abacus at home, let your child copy it.
What PlayBuddy and PlayType say
PlayBuddy: “Zero is a number too. Let's find it!”
PlayType: “No beads on the bar? That's zero. We call it clear.”
PlayBuddy: “Close every finger. Your hands show zero!”
PlayType: “To clear, send the top bead up, and the bottom beads down!”
Stars
Three stars for up to 1 slip in 13 answers, two stars for up to 3.