The mandi package provides commands for typesetting symbols, expressions, and quantities used in introductory physics and astronomy. Many of the commands are inspired by Matter & Interactions by Ruth Chabay and Bruce Sherwood. Many of the astronomical commands were inspired by my own classroom needs. It must be understood that mandi does not do any computations! It only provides commands for typesetting. Run the file mandi.dtx through (pdf)LaTeX to generate README (this file), mandi.ins, mandi.sty, vdemo.py, and mandi.pdf (user documentation). I assume a TeXLive2011 or later distribution is installed.