Worksheets containing lessons and answers for sixth-grade science are found on MrNussbaum.com and at SchoolofDragons.com. HelpTeaching.com also allows a student or parent to build custom practice tests for sixth-grade science.
HelpTeaching.com also has an online assessment test, so a student can get a sense of what areas he needs to focus on. Further sixth-grade science answers are found online at MissDoctorBailer.Com. These lessons include video lectures and demonstrations.
At this level, students are frequently expected to participate in a school science fair. For help with choosing and completing experiments, Education.com has a wide variety of experiments for sixth-grade science fairs, complete with material lists, directions, and the lessons conveyed with each project.
Science vocabulary also gets more sophisticated at sixth-grade level, which makes SpellingCity.com a helpful website for a sixth-grade science student. This website contains a spelling list of common sixth-grade science vocabulary.
Curricula vary from state to state, so it is best to get a copy of the appropriate syllabus from the student's school or teacher. It is also helpful for the parents to talk to their child's teacher before beginning revision work at home so that the teacher can point out weak areas where the student needs more practice.