# Math Block Set Guide blocksetguide_min_r3 PDF - Page 5

How many and how many make 10? Guess Composition & Decomposition of Numbers how many There are two ways to see the structure of a number – composition and decomposition. Composition is the way of seeing the number “7” as “3 and 4 make 7,” whereas decomposition is the are way of hidden. seeing “7” as “7 is made of 3 and 4.” Both of these ways are crucial in learning addition and subtraction. Particularly, understanding the structure of the number “10” is essential in grasping the fundamentals of base-10 concept, and can be used for addition and 7 1 subtraction greater than 10. and and Have 10 math blocks ready. Hide some inside the case and have students figure out how many are hidden by looking Let’s make 10 at the ones that are not cased (refer to Image 1). In the beginning, you’ll want to use the clear case (Image 2). When students become used to the idea, switch to the opaque case (Image 3). How many mo How to Use the Japan Math Block Set Date n i t Image 1 5 Try t and First, let’s play with ! Let’s see... 4 and what number make 10? 4 Guess how many are hidden. 2 10 a a a Let’s make 10! How many more do we need to make 10? and Why Choose the Japan Math Block Set? Students can visually grasp the structure of 10! 4 8 6 4 3 9 Image 2 Image 3 and and and Since composition and decomposition of 10 is important for numbers 10 or greater, manipulation of the blocks can and and familiarize students with the structure of 10 by making them see how many more is needed to make 10. Students can instantly compose and decompose 10! Un i t and 71 By taking steps – first using the clear case, then using the opaque case – students can slowly learn the idea of 9 composition and decomposition of 10. and 3 and Students can instantly compose and decompose numbers up to 10! Understanding what 10 is made up of through the math block manipulation makes it easier for students to instantly 6 5 find, for example, that “It is 7, so I can make 10 with 3” or “10 can be split into 2 and 8, so it is 2.” This is the result and and of manipulating the educational material, the Japan Math Block set, by their own hands and actually experiencing and 6 70 making sense of the structure of 10. Students can see and feel the numbers that construct 10 from multiple perspectives. 70 For more information, check out japan-math.com and 5