We are glad to join with you in prayer for your brother's academic success. It's wonderful that you are seeking God's help in this matter. Let's pray:
"Dear Father,
We come before You in the name of Jesus Christ. We lift up the brother of our friend and ask that You would grant him success in his schoolwork. Help him to understand all subjects and to do well in his studies.
God, You tell us that if we lack wisdom, we can ask of You, and You will give it to us liberally and without reproach. James 1:5. We ask for Your wisdom and understanding for our brother. Guide him in his studies and help him to stay focused and committed to his work.
Help him also to be a light for You in his school. Let his conduct and attitude be a reflection of Your love and grace. May he be a positive influence on his classmates and teachers.
Lastly Lord, we pray for his spiritual growth. Help him to know You more and to walk in Your ways. Help him to learn and grow in the knowledge of Your Word, the Bible.
We pray this in the name of Jesus Christ, the only way to approach God the Father. It is in Jesus that we are saved, by confessing our sins and believing in our hearts that Jesus was raised from the dead, we will be saved. Romans 10:9
Amen."