Does 9th, 10th and 11th grade marks matter in US universities?

Yes, your 11th standard grades matter. An undergrad student typically applies to
Universities while they are in the 12th grade. Since you will not have 12th standard
board results, your 11th-grade scores become essential. That being said, US
Universities are aware of the grade deflation in the 11th grade.
Not only your 11th standard scores but your 9th and 10th-grade marks will also matter.
So keep your grades high from 9th to 12th grade. Consistency is the key.
You also have to submit your 12th standard mid-term grades. If your scores are less in
your 11th grade, work hard and show your improvement in your 12th standard mid-term
semester.
Then there are test scores, essays, resumes, recommendations, community service,
extra-curricular activities etc.
Your 11th grade is just a part of your application and not the sole criteria for your
admission decision.
However, if your 11th-grade scores might let you down, you can ask your school to
make a report card showing your marks and percentile rank. The percentile will show
your standing in the class- like you are in the top 10% or 20%.
Also, you can make up for your low scores by giving the SAT Subject Tests or the
Advanced Placement Exam.