I have almost 11 years of teaching experience. I myself an Engineer and I have a complete command of subjects such as Mathematics, Physics, Chemistry, English and other subjects. I have taught around 100s of students during these 11 years of experience. The majority of them have gained A* and A's in their examination.
I would put my 100% on your child and if you child shows a little interest and work harder as per my instruction than s/he would be able to gain a better result as compare to their previous result.