### Teaching and Group Activities for Understanding

**Day 1 Teaching**

Show children birthday cards with ordinal numbers. Ensure these include 1st, 2nd, 3rd and discuss how these are said and written differently. Children say these numbers. Look how 21st is written too. Show how ordinal numbers are written/said.

**Group Activities**

Use the ‘Racing Riddles’ in-depth problem-solving investigation below as today’s group activity.

Or, use these activities:

-- Describe multi-coloured cube towers using ordinal numbers.

-- Work out secret messages using ordinal numbers.

**Day 2 Teaching**

Place 2-digit numbers on a large landmarked line. Discuss where different numbers go – between which multiple of 10. Make a flexible equals sign (see teaching) and then use this to demonstrate =, < and > with towers of cubes.

**Group Activities**

-- Record inequalities between two 2-digit numbers, using symbols for inequalities.

-- Pick 2-digit numbers to complete inequalities, using symbols for inequalities.

**Day 3 Teaching**

Write 32 on a tag, and ask a child to hang it after the 32nd bead on a 100 bead bar. Discuss how 32 is nearer 30 than 40 and explain that, if we are approximating, we round it to 30. Model how 37 rounds to 40. Continue with different numbers including 35, 25, 75 and 95.**Group Activities**

-- Make 2-digit numbers and round them to the nearest 10.

**Day 4 Teaching**

Show children items priced: 17p, 25p, 32p, 49p, 55p, 63p, 74p, 86p and 99p. Round each to nearest 10p. Mark each on a 0-100 landmarked (in p) line. Discuss how 99p rounds to 100p which is £1.**Group Activities**

-- Identify numbers that will round to a given 10.

-- Round prices to the nearest 10p to keep a running total.