More Abacus Madness

I've been tinkering with ideas for an abacus that hybridises the Montessori place value colours with the RightStart Math Al Abacus... I liked the idea that Joan Cotter uses the reverse side of her Al Abacus for trading exercises with twenty beads for each place value, enabling you to demonstrate trading occuring after the second addend. So here's my hybrid:

But now I'm not so sure that I like the idea of twenty beads per place... could it be confusing?

I shall have to play with it for a while.

Montessori Large Bead Frame/Alabacus hybrid

Today I was using the excellent Montessori Math album from Cultivating Dharma to introduce the Large bead frame lessons. I don't own a Montessori Large Bead frame, so I adapted the Alabacus from RightStart Math. I'd like to make my own large bead frame based on both. Perhaps with the unit beads as 5 dark green, 5 pale green, and the tens beads as 5 dark blue, 5 light blue, etc.,(corresponding to the Montessori colouring, but retaining the pattern of the Alabacus.)

 The bead frame paper was a download also from Cultivating Dharma.
To emphasise the number families (thousands, millions and so on) I adapted a Waldorf based idea on teaching place value from Little Nature Nest, and adapted a math story called "Infinity Street" but changed it to "Infinity Forest".

These are some pictures from previous lessons, before introducing the Bead frame: