Thank you for the tips. I will sign him up for the SAT. Does taking it too many times look bad for your application to college?
I did some more research and found a math and grammar study book for him to go through. He already started the math book. He took the grammar book today to school. (Hopefully he opens it. He prefers math.) He is motivated to get a good scholarship so I am pleasantly surprised that he is voluntarily starting to study. Getting test results hopefully will encourage him to study more and getting a higher score.