Mary is great and my son is very happy with her. She is knowledgeable, easy to understand and knows about the SAT test which is paramount for us. She knows how to work towards understanding the test and recognizing the kinds of problems that the test will contain. My son has been taking lessons only for a couple of months, but he has seen a drastic improvement in his understanding of the Math material and applying it to the SAT test. She is flexible with her hours as well. I feel that Mary is the the key to my son feeling comfortable and doing well on his SAT's. I would highly recommend Mary for a math and SAT prep tutor.