Free math fact fluency app with three-to-five minute daily sessions and spaced repetition.
MathBuilders is a math fact practice tool for addition, subtraction, multiplication, and division. Sessions are three to five minutes, with a three second per fact recall threshold so a slow correct answer is not counted as known. Missed facts come back at widening intervals via spaced repetition. Stop anytime without losing progress. Built by a parent for his own kid after the popular options either dragged sessions out too long or did not actually adapt to the facts the child needed more reps on. Basic tier is free, premium is available.
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