Even though all the kids are in the same math class, they all have different abilities.
The skill level of the students in the math class varies from student to student.
ーEven though all the kids are in the same math class, they all have different abilities.
「みんな同じ算数のクラスにいるけれど、異なる能力を持っている」
math class で「算数のクラス」
to have different abilities で「異なる能力・技量を持つ」
ーThe skill level of the students in the math class varies from student to student.
「算数のクラスの生徒の技能レベルは生徒によってそれぞれ異なる」
skill level で「技能レベル」
to vary で「異なる」
from student to student で「生徒によってそれぞれ」
ご参考まで!