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1.17 Composition and calculation: 100 and bridging 100

Created on 04 June 2018 by ncetm_administrator
Updated on 04 June 2018 by ncetm_administrator


Explore the additive and multiplicative composition of 100; draw on known strategies and number facts to calculate across the 100 boundary.

Teaching points

  • Teaching point 1: There are ten tens in 100; there are 100 ones in 100. 100 can also be composed multiplicatively from 50, 25 or 20, units that are commonly used in graphing and measures.
  • Teaching point 2: Known addition facts can be used to calculate complements to 100.
  • Teaching point 3: Known strategies for addition and subtraction across the tens boundary can be combined with unitising to count and calculate across the hundreds boundary in multiples of ten.
  • Teaching point 4: Knowledge of two-digit numbers can be extended to count and calculate across the hundreds boundary from/to any two-digit number in ones or tens.



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26 June 2018 16:20
Can the years 3, 4, 5 & 6 resources be zipped for easy downloading like the year 1 and 2 resources please (or the whole lot in one zipped folder?)
By dfmoorse
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