Big Friends Bridge — Lesson 41: Plus 9 and plus 8 practice

What your child does, card by card

Plus 9 and plus 8 practice. Practice day! PlayBuddy opens the lesson: “Practice time. Let's get quicker and better.”

First a reminder (“Plus 9: 1 off. Plus 8: 2 off.”): the beads build 7, 6, 16, 7, 5 and 15, ring by ring, while your child watches. Then one ten goes on, both times.

Try it: your child works out 4 + 9 and 3 + 8, with a green ring on the next bead to move.

Five in a row: a mission of 8 tasks with a count of right answers in a row, with the best kept. Your child must work out 2 + 9, 4 + 8, 8 + 9, 9 + 8, 1 + 9, 2 + 8, 6 + 9 and 7 + 8.

Copy me: the beads show 16, 12 and 17 and your child answers by tapping the drawn fingers, the hands window glowing.

Then the beads hide and the sums 8 + 9, 3 + 8 and 6 + 9 are done in the head, the answer shown on the fingers.

You're ready! Plus 9 and plus 8, with the big friend.

What this lesson trains

16 answers, roughly five minutes: 20 bead moves, all with bottom beads. Numbers reach 17, so the tens rod and the ones rod work. Then 3 quick looks in your head. 10 of the 10 sums need a big friend (“+9 = −1 +10” and “+8 = −2 +10”); the others use free beads.

The first thing your child does: work out 4 + 9 and 3 + 8.

Fingers and hands

Below the abacus the drawn hands show zero and 1, 2, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 15, 16 and 17 here, finger for bead: the left hand counts the tens, the right hand the ones.

+9 on the fingers: the right hand lets 1 go and the left hand opens one more finger for the ten (−1 +10). +8 on the fingers: the right hand lets 2 go and the left hand opens one more finger for the ten (−2 +10).

In Copy me the beads lead with 16, 12 and 17, and your child answers on the fingers: the reverse of making a number on the beads.

What PlayBuddy and PlayType say

PlayType: “Ten is one too many. So take one off first, then add the ten!”

Stars

With 1 or fewer slips across the 16 answers your child earns three stars; 4 or fewer, two.