putting on an act to deceive or fool his parents

Kang Kang is a lazy bone and does not work hard at his lessons. However, whenever he stays home, he is being busy with his homework, actually just going through the motions or merely putting on an act to deceive or fool his parents.  As it stands, Kang Kang has never really sets his schoolwork in motion. It is no doubt that he is a backward student with poor grades. 
 康康是个懒虫，不努力做功课。然而，每当呆在家里，他都会装模作样忙着做作业，实际上只是做做样子（走过场），糊弄父母罢了。既然这样，康康从未真正重视学业。毫无疑问，他是成绩极差的落后生。

So keep in mind such a saying: You can fool your parents sometimes but you can't fool them all the time by making believe you are pursuing the goal expected by them. 
所以请记住这句话：有时候你可以愚弄父母，但你不能靠假装为实现他们所期望的目标而在努力来欺骗他们一生吧。
 
a lazy bone: 懒虫；懒汉；懒骨头
work hard at：努力学习；努力做；在.....方面努力学习
make believe (that) : 假装；装模作样
go through the motions (of doing sth): to do or say sth because you have to, not because you really want to ;pretend to do something by acting as if one was really doing it 做姿态；走过场
set/put sth in motion 让…动起来to start sth moving 
as it stands/As it was : 其实是…; 按照现在情况；根据目前情况来看；事实是这样
林肯的名言:  You can fool some people sometimes, but you can't fool all the people all the time.
你可以在某些时间欺骗某些人，但是你不能在所有的时间里欺骗所有的人。