Left Hand Dev

Web tools for learning math and statistics.

Left Hand Dev builds browser-based tools and study resources for students and the teachers who use them.

See the projects
The rāSHio homepage: an online statistics calculator with a list of twelve tools including t-tests, ANOVA and chi-square. The bookSHelf homepage: a library where you pick a textbook and open a section.

Two projects

Each one runs in the browser with nothing to install.

12statistics tools

rāSHio

An online statistics calculator for introductory statistics. Run t-tests, z-tests, ANOVA and chi-square, work out confidence intervals, and build histograms, box plots and scatter plots. You can open the preview without an account.

Open rashio.app

187sections to read

bookSHelf

A library of textbooks, including Integrated Math 1, Introduction to Statistics and Calculus Volume 1. Pick a book, open a section, or search across all of them.

Open oerbookshelf.app

About

Left Hand Dev is a small independent project run by one developer who writes software for the classroom.

The goal is simple pages that do one job well. A student should be able to open a tool, see the result and get back to the homework. Both projects above are live now, and this site is the home for them.