Solution:
Standard units:
Standard units are the units we usually use to measure the weight, length or capacity of objects. The standard (metric) units that would be discussed at primary school would include: grams and kilograms, centimetres, metres and kilometres, millilitres and litres
Non-standard units:
Non-standard units are used by children in Foundation Stage (Nursery and Reception) and Year 1, to introduce very young children to the concept of measuring without them having to read any scales. Reading scales of any kind is a challenging skill in itself, so the idea of non-standard measures is to focus the child on the concept of heavier, lighter, longer, shorter, etc. before they go move onto the next step of measuring using standard units.
The Advantages of Standard Unit are:
It helps everyone to understand measurements in a set of unit systems.
SI units are derived from one another without the use of conversion
SI is a metric system. The disadvantages are that the SI unit talks only about one unit. Hence other units' importance was diluted.
Pinches, handfuls, spoonfuls and bottles are non-standard units because they do not have actual measurements and Their measurements are not constant at every given time, They change.
They are measurements used to put through kids growing up before they learn how to work with the standard units of measurements
They do not have constant conversion rates also and as such they are non-standard