Recognize and use structures in number recognition (e.g. 1000 as 10 H or as 100 T).
Use the structure of the decimal system (bundling, place value) in a planned and systematic way and justify relationships between different number representations (e.g. place value notation, graduated notation:
734 → 7H 3T 4U, number word, units cube / tens bars / hundreds plates), to be able to use the decadal place value system with confidence.
Compare spatial contents of simple solids by building with unit cubes and by counting unit cubes.