### Teaching and Group Activities for Understanding

**Day 1 Teaching**Discuss how to measure the height of a child, reasoning that it is easier to do this with them laying down. Pass round 1cm cubes, then show a decimetre strip. This is a decimetre, 10cm. It is useful for measuring things. Pass round several strips. How many decimetres long is Annie? Children estimate. Use the strips to measure the child.

**Group Activities**

--Measure objects using decimetre long card strips as a standard unit of measurement.

--Measure people using decimetre long card strips as a standard unit of measurement.

**Day 2 Teaching**Look at decimetres and centimetres. Discuss how they are always the same length. Lay ten 1cm cubes along 1 dm. Draw round your foot and measure its length in cm, counting in 10s and 1s.

**Group Activities**

--Measure objects in centimetres using decimetre long card strips cut to length.

**Day 3 Teaching**Show a 30cm ruler. Explain we can measure using rulers. Point out the cm. Demonstrate how we can measure things longer and shorter than a decimetre using the cm marked on the ruler. Estimate and measure classroom objects.

**Group Activities**

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

Or, use these activities:

**--Estimate and measure classroom objects.**

--Estimate and measure distances in m and cm.