DeltaMath
DeltaMath is a math practice platform for middle and high school classrooms, with automatically graded problem sets and instant step-by-step feedback. A New York City algebra teacher wrote it in 2009 for his eleventh graders, and problems still regenerate their numbers so no two students can copy.
Why it earned its spot
The homepage works from a narrow palette — navy, one mustard yellow, white — and the hand-drawn underline beneath “right” is the only emphatic mark in the hero. A pale blue band underneath switches register entirely for the at-home audience, with a line-drawn triangle mascot waving beside a lightbulb and an A+ sticky note. The three feature columns sit in unusually generous whitespace, short centred paragraphs under thin outline icons, and the testimonials carry real names and towns rather than district logos. It closes on a dark band where the running count of problems solved is set in separate digit tiles, odometer-style: 13,476,568,063.
The colors
Belongs with
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