One of the things Asterix and Obelix comics exposes the children to is Roman numerals, and since I think those are important to understand we’ve spent some extra time working on them. Today’s activity started with rolling two dice and writing down in Roman numerals whatever score we rolled, talking about the number in relationship to fives. My little guy decorated the paper as a race-track and to make it into a race game, but there was no real competition simply looking at the number and writing it down. As we do, we review numbers. Seven is five and two. Eight is five and three. I love how Roman numerals highlight these connections, so important to make. Four – that’s one before five. Nine is one before ten.
Next I made out a simple abacus board. A few years ago (when my oldest son was the age second son is now) I read the book The History of the Abacus by J. M. Pullan and realized that abacus don’t need to involve beads and wires. Some where counting boards, with different locations marked off. So I made one, marking off rows for I, V, X, L and C. The 5s and 50s I indent slightly to show they are different from the other three. Then we rolled dice, adding the numbers to keep a running total.
The game goes something like this. Someone rolls a four and puts four markers out. When the next person rolls a three he’ll have to put three markers on and I’ll comment that “it’s too crowded there… only four markers allowed on that row.” Then five markers are removed and one marker is placed in the next row. We keep going until our collective total reaches 100. The indent rows have to be cleared so they hold only a single marker. Next time I’ll have him keep track of the totals on a calculator too.