The game is mainly for primary school grade three，corresponding the third grade seventh unit of primary school mathematics of Human education--rectangles and squares.In the first grade, weve known a few simple graphic shapes.Now lets have a deeper understanding of the characteristics of rectangles and squares and calculate their perimeter.The game is divided into four levels.The first pass is the cognition of the quadrilateral.Second off is a rectangular square and a number of other graphic graphics.The third is the perimeter of the understanding of the concept of graphics.The fourth pass is the calculation of the circumference of the rectangular square.Little friends, come on to the challenge!QD learn aims at teaching through lively activities and happy learning.