The Mailbox? Superbook Grade 5 is your complete resource for an entire year of success. Reinforce and enhance your fifth-grade curriculum with creative, fun-filled lessons on basic skills. Choose from grade level-appropriate, original, and kid-appealing reproducibles. This great collection of year-round materials is the one resource that you can't be without - ; a great back-to-school buy! Grade 5. 320 pages.