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it features tight integration of text and graphics, which reduces skipping back and forth; and  it implements margin notes, which we use for quick reminders of mathematical formulae and side remarks. A sample page, from the notes on coordinate systems, is shown in Fig.~\ref{f.sample-handout-page}. Sketches for the handout were made on an iPad using the \href{https://evernote.com/penultimate/}{Penultimate} app.     As can be seen on the sample page, in Fig.~\ref{f.sample-handout-page},  exercises are incorporated into the body of the notes. Typically a few exercises are assigned prior to the start of lecture as guides to reading the notes. Longer, more involved problems are then assigned as homework following the lecture. Solutions, which are written in the same format as the lecture notes, are distributed when the marked assignments are returned. The solutions are discussed in lecture, with ample opportunity for students to ask questions.