Importance of Estimating in Real Life   A lot of everyday maths is about estimating quantities and I will be talking about some strategies including Kinect that can be used to develop a sense of number considered a very basic arithmetic skill needed to estimate. Forest Way Teaching Alliance 2nd October 2015

essential life skill make judgements can save time & money uses mathematical knowledge & reasoning enables us to check reasonableness of calculations . ‘front end’ estimates e.g. 575+ 324= 900 provides fun & rich & maths activities Do we give it enough importance ?

skills of estimating develop over time and practice learners need to develop sense of number, physical quantity, & units of measure need a comparison need to understand context challenges

Learning to estimate is dependent on the acquisition of very early arithmetic skills To develop sense of number is to be able to enumerate small quantities then progress to finding out how many without counting each individual object.

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Small containers same width as the jars Count items in small container – use multiples of 10 Point out the height of the items in the small container.  Then speculate “how high” the large jar is in comparison to the height you measured in the small container.  Model the height of the small container using fingers. Learners do the same to ‘count’ height of the large jar, and then count in 10’s to get to the approximate answer. Show that 3 and a half small containers stacked up would equal the height of the large jar so 10+10+10+5=35 would be approximately how many were in the jar.

Describe capacity using own words Fill containers with liquid or objects to show capacity approx. half full, nearly full, nearly empty or use fractions Calculate approx. quantity in containers using the approach in previous slide.

A giraffe is about 5m tall Estimate the height of the bus. Estimate height of young giraffe

1 kg 49p £1 £1 medium 50p 60p £3.50 £1. 35

Kinect Use technology to provide engaging opportunities to practise estimation and support relationship between estimation and numbers by embodying the relationship in whole body movement along a a virtual number line. Relationship between learner’s movements and number tracked and presented on screen by P. Choak’s specially designed program for Kinect.

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http://www.mathsisfun.com/numbers/estimation-game.php http://resources.oswego.org/games/Estimate/estimate.html http://www.iboard.co.uk/iwb/Estimate-and-Count-Marbles-402

‘Interactive investigation estimating different capacities in unusually shaped containers.  These widgets engage visual learners who may struggle with text-based or traditional teacher-led lessons. For kinaesthetic learners, a range of open-ended investigations and problem-solving tasks link mathematics to the real world.’

References BBC Skillwise website Estimating & Rounding. Nasen Special 3/12 An Educated Guess Number Sense Series: Developing Early Number Sense –nrich.maths.org