I thought I would share the work we did with subtraction memorization.
We did not spend a large amount of time with the subtraction materials, and we also added in iPad apps for practice. Xander was keen to head into multiplication which is a large section to cover.
He preferred to work with random booklet equations and equation tiles after the initial presentations, as I had mentioned we did with addition.
Our setup in terms of ruler placement was comfortable for us, but you may choose to set yours up according to your manual. I have seen a few different methods of setting up the boards. We did not find it useful to layout the natural rulers above as they were hard to reach on the floor or on the table.
We did keep them arranged in the box above.
This how we started with ours.
This method made sense to us, but Xander decided to change it further to suit him.
Xander also decided to stop using the natural wooden rulers to cover unused numbers (or minuend as some recommend). He simply used the blue ruler to lay in the subtrahend to discover the difference (normally the red ruler would be placed to show the difference/answer). As with all lessons we have made them our own. These little discoveries that Xander has made are shaping his journey and making it interesting and fun for him.
I am happy to follow along:)
Similar to addition we also worked with bead bars for practice in formats for subtraction.
We have since created all of the memorization materials together with the formats for operations cards (seen below) and word problems. The materials I created follow the sequence and work covered in our
We used the Strip Boards fairly early on to play around with the the basic concept of addition and subtraction. Later though there are a sequence of lessons in our manual that utilizes both the Working Charts and Strip Boards together. We used the Charts for initial presentations as well, but little after ward.
Part of the subtraction sequence (as with the others) he worked on simple word problems. Again the word problems for Xander were (for him) about fact practice, but mainly about organization and writing practice.
Below are the memorization materials that are used in our manuals for subtraction. We do own the boards and during Xander's work we used charts, and various materials I found online (there are many), but I found it confusing initially to find and figure out all of the materials needed for each sequence given the boards do not come with any of the materials that are used to work with them.
Part of the subtraction sequence in our manual is the Subtraction Snake Game.
The Montessori Snake Games are chatted about frequently online. When we were making the decision as to weather we would purchase the snake games we decided to only purchase the Subtraction Snake Game. Mainly because we could use it for addition and multiplication as well. We have not yet worked with the Negative Snake Game.
We did not spend large amounts of time with the Snake games, but your child may wish to.
Laying out a subtraction snake.
The subtraction snake game is basically the same as addition - exchanging for golden ten bars and using the black and white stair as place holders , and then subtracting when encountering a grey bead bar (grey bead stairs). Here is a great visual step by step of the game. You will need to scroll down to find it. Your manual will detail it for you as well.
Xander verified his work in two ways. Again you may wish to do this differently or have different bead placement, but this is what he came up with that made the most sense to him.
The bead bars can be troublesome to lay out because of the copper loops, so he is pairing them side by side to avoid the loops. Below he is writing the subtraction problem by adding up the colored bead bars and grey bars.
If you missed our Addition Tables work you can visit the posts below.