Students build addition fluency through three progressive visual modes: a 100s chart where colored squares represent addends, a guided number line for practicing systematic addition strategies, and a flexible number line where students choose their own approach. Supports TEKS 2.2.A, 2.2.B, 3.2.A, 3.2.B, 3.2.D (place value and addition strategies).
Skills: place value, number line reasoning, addition strategies, mathematical flexibility. Grades 2-3. Features progressive difficulty and immediate feedback.