### Planning and Activities

**Day 1**Add 10, then 20, to 2-digt numbers, using Spider on a 1–100 grid. Begin with multiples of 10, then any 2-digit number. Record number sentences. Extend to adding 30.

**Further Teaching with Y2**

Use place value cards to model addition of pairs of 2-digit numbers by partitioning, e.g. 34 + 23, 45 + 24 (1s total less than 10),

then 46 + 25 (1s total greater than 10).

**Group Activities: T with Y2**

Y1 -- Choose 2-digit numbers and roll a dice to add 10, 20, or 30.

-- Pick a number on the grid and roll a dice to add up to 6 tens.

Y2 -- Play a card game to practise adding two 2-digit numbers.

**Day 2**

Add 10s and multiples of 10 on 1–100 grid.**Further Teaching with Y2**

Children choose when to add 2-digit numbers by partitioning and recombining or by counting on in 10s and 1s. Discuss several examples and consider choices made.**Group Activities: T with Y2***Use the in-depth problem-solving investigation ‘Dicey Addition’ from NRICH as today’s group activity.*

Or, use these activities:

Y1 -- Add a multiple of 10 to add to a number; record in a number sentence.

-- Calculate the missing number in an addition number sentence.

Y2 -- ‘Work backwards’ to suggest pairs of 2-digit numbers that add to make a given total.