These Montessori style hand-on subtraction activity ideas are great for preschoolers and young children who need plenty of experience with concrete materials to consolidate basic mathematical skills. (See my last post for more info.)
As with the addition trays, the subtraction facts that the child has already memorised are added to the screw-top jar to provide a visual indicator of their progress.
Initially, the subtraction problems are split into sets; subtract 0, subtract 1, subtract 2 and so on and only 1 set is out at a time. Once they know the sets fairly well individually, we combine the lot, taking out the ones they have mastered and working on what is left. As with addition, learning to take away 0, 1, 2, and 10 is very easy, so starting with these gives the child a boost of confidence as they quickly master the first sets, filling that jar almost immediately.
The subtraction materials are set out as above. The first and last plate are deliberately different from the second to provide a visual reminder of the relationship between the two. Subtraction must be done in order (numbers are not interchangeable as they are for addition and multiplication problems) so the child first counts out the number of objects they are starting with into the first plate. The smaller plate shows what has been taken away (removed, subtracted etc.) and what is left on the first plate is scooped over to the final plate, providing the answer.
When the novelty of the plate tray wears off, I present the subtraction problems the child has not mastered in different formats to provide extra practise and revive interest in the activity.
It doesn’t take too much extra time or effort to keep learning engaging and enjoyable. Have a look around your house or check out your local discount variety store for a couple of different kinds of manipulatives and you are on your way.
Posts you may find useful:
List of useful materials to collect and buy for hands-on tray activities
Building focussing and concentrating skills in toddlers
Workboxes – homeschooling multiple ages
Surviving new babies, sick kids and interruptions