The 13-year-olds got the call up for the WA team after successful State Championships and impressed selectors at development sessions and mini meets that followed.
Scotch College student Callum won a gold medal in javelin and silver in triple jump, while Amy, of Floreat, brought home silver in the 4x200m relay and bronze in the 200m.
The duo helped the WA team of 22 athletes finish 2nd overall.
‘At little athletics there’s not as much competition so I had to push myself a bit more at the Nationals,’ Amy said.
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Callum, who recently broke his arm playing rugby for Scotch College, said the Nationals gave him confidence to compete in other competitions.
The teenagers, who won UWALAC top under-13 girl and boy and senior champion prizes this season, are aiming for selection at the competition between Singapore, Malaysia and WA that will be held in Singapore next year.