# Math & Money

The girls are finally at the moment where they are very interested in money.  We recently had a lesson on the different types on money in a general sense from coins to paper…etc. I compared the different bills in money to their decimal system tray and they seemed to have a good first understanding of the comparison.  Today we took out the introduction to the decimal system tray again but we added the ‘fetch game’ to our lessons.  I pulled the units (representing ones), Tens, Hundreds and thousand blocks out and lined them on the table as the ‘Bank’.  I labeled each for visual reminders and also to help with the symbolic nature of learning the symbols themselves.  I then gave the girls a  tray and a simple number from each of the decimal values…100, 200, 10, 20, 1-9, 1000,2000 etc.

Today what we did with that was ‘build a number’.  Then we broke that number down and saw it in it’s parts.  Then rebuilt it to understand the place values we were reading.  I am noticing that the girls have a harder time verbalizing the written symbol versus understand what the number actually represents.  They seem to understand the quantity much more naturally.   Future activities will include variations of this with the ‘fetch game’. Where will be given a number from each of the place values example 2345 and be expected to build that number in visuals.  Or vice versa.  This is also helping them with addition and writing formulas such as addition problems down as they are learning how to line up the numbers according to their place values by naturally catching on to the quantity of numbers (or place values) a number has.

Math materials pictures above are representing thousands, hundreds, tens, and units (ones).  You’ll see an abacus there too which has coordinating place values.  On the floor are the number rods that I like to do simple math with and building the formula next to them with the math box pieces that are sitting next to the rods.  Or we use the chalkboard.

Lily is counting units to match the number she has been given.

The girls working on matching up their quantities.

After working with the ‘fetch game’ we moved onto the cash register where the girls got to put to use their decimal system skills they have been learning.  We set up a grocery store and a bank (because using the wallets became too much at one time-and it was easier to see the bills laid out in a drawer rather than wadded up in a wallet).  We started out as a dollar store where everything was a dollar and the girls took turns being at the cash register and as a customer.  They gave exact change as it was one dollar bills.  Then we started varying the prices and the amounts became more challenging.  They began subtraction at this point.  But instead of deciding on the register (calculator) or figuring the amount out in their heads or on their fingers we included the abacus to give them a visual of subtraction.  And we discussed the steps of problem solving to understand the answer.  That we use simple addition to add up the items and if the money we are given is more than the amount then we subtract.  The girls have not used the addition snake game often (Montessori) so we are learning how to exchange numbers and quantities through our money game.  So they are understanding that 5 and 5 is 10 and the same works with money.  And they are learning that everything has a worth to it.  And that that worth is a certain number.  So this particular activity has reached a lot of areas.  And there are many more areas to learn from it.