The game is mainly for primary school grade three，corresponding the third grade first unit of primary school mathematics of Human education--hour minute and second.Do you remember the time you studied in grade one?At that time we only knew the whole point and the half point.Now we need to know the second ，the conversion between the seconds and simple calculation.Are you ready？Lets happy to learn in the game!QD learn aims at teaching through lively activities and happy learning.