Some of the most successful maths teaching approaches in the world place a strong emphasis on building children’s understanding through a carefully structured progression from concrete through pictorial to abstract.

This can easily be achieved by:
engaging young children in exploring mathematical ideas using counters, cubes, blank and numbered counting sticks, paper folding, etc
introducing children to a ‘vocabulary of diagrams’ and helping them to use these consistently to explore and then to explain the concepts they have been learning (eg number lines, number bond diagrams, bar models, arrays, etc)
encouraging children to record diagrammatic representations and numerical calculations together when explain their solutions to a problem

Much of the guidance and many of the activities on the Maths Without Limits website show how to use both practical materials and diagrams in different contexts. Here are some examples.