CREATE TABLE table_50064 ("Year" FLOAT, "Award giving body" TEXT, "Category" TEXT, "Nominated for" TEXT, "Result" TEXT)

What's the category for the tween academy: class of 2012 nomination?
SELECT "Category" FROM table_50064 WHERE "Nominated for" = 'tween academy: class of 2012'
SELECT "Category" FROM "table_50064" WHERE "Nominated for" = 'tween academy: class of 2012'