School effectiveness is primarily determined by school-level factors including having a guaranteed curriculum, challenging goals with effective feedback, parent/community involvement, and a safe learning environment. A school must also foster collegiality and professionalism among teachers. While the curriculum has the greatest impact, it can be difficult to implement properly. Teacher effectiveness is influenced by the instructional strategies, classroom management, and curriculum design they employ. Finally, student achievement is affected by their home environment, intelligence, background knowledge, and motivation to learn.