Yes the scores are fine, can be a little higher. Although many of the schools look at the percentile rather than the raw score.
But only the scores will not get you into a good boarding school. They also need to look at grades, teacher recommendations, extracurricular activities, essays and interview.
These schools do not only look at your SSAT and TOEFL scores. The other important factors are grades, interviews, teacher recommendations, English standard, essays and extracurricular activities. Many students who apply there have the same SSAT and TOEFL scores. In fact, I just had a conversation today with one of the admissions people at Milton and what is important is how the student is overall, not just test scores.
