<p>Where STEM stops being a theme and starts being a subject. Teen-tier books cover the material that actually shows up in middle school and early high school — algebra, chemistry, physics, coding logic — with the worked examples and practice sets a student needs to get fluent, not just familiar.</p><p>Answer keys included. Written to be worked through with a pencil, alone, at a kitchen table.</p><p>Available as an instant PDF download or a printed, bound copy shipped to your door.</p>