DotSense is made by Gabriel, a teacher with a background in mathematics education. The idea came from a simple frustration: there are plenty of free virtual manipulatives online, but they all leave the hard part — the planning, the timing, the questions — to the teacher. You still have to know which numbers to show, how long to show them, and what to ask afterward.
Routines, not manipulatives
DotSense flips that around. Every tool runs a complete instructional routine — Flash, Wait, Ask, Reveal — with the timing, the discussion prompts, and research-based number ranges already built in. You press one button and teach. It's the difference between being handed a pile of base-ten blocks and being handed a lesson.
Research first, always
Nothing here is decorative. The design of each tool traces to specific research: perceptual and conceptual subitizing and learning trajectories (Clements & Sarama), groupitizing through equal subgroups (Starkey & McCandliss), number-line estimation that predicts and trains achievement (Siegler & Booth), fluency as accurate-efficient-flexible rather than fast, and the IES/WWC practice guide on systematic instruction, representations, and number lines. The fraction suite is built specifically to prevent and dislodge whole-number bias, the well-documented misconception where students treat a fraction's numerator and denominator as two separate whole numbers.
Free, and safe for your classroom
Every tool is free and works with no login. There are no student accounts and no student data is ever collected — the tools run entirely in your browser, which keeps them well outside COPPA and FERPA scope. They're designed teacher-facing, for your smartboard, with a dark or light theme and a projection mode that hides the controls.
Get in touch
Questions, ideas, or a routine you wish existed? Email dotsensemath@gmail.com.