\documentclass{article}
\usepackage{pdfpages}
\begin{document}
%\includepdf[pages=3]{S0.pdf}
\includepdf[pages={1-},angle=0,landscape]{L17.pdf}
%rotateoversize
\includepdf[pages={1-}]{L17classnotes20170321.pdf}
\includepdf[pages={1-},angle=0,landscape]{L18.pdf}
%rotateoversize
\includepdf[pages={1-}]{L18classnotes20170324.pdf}
\includepdf[pages={1-},angle=0,landscape]{L19.pdf}
%rotateoversize
\includepdf[pages={1-}]{L19classnotes20170328.pdf}
\includepdf[pages={1-},angle=0,landscape]{L20.pdf}
%rotateoversize
\includepdf[pages={1-}]{L20classnotes20170330.pdf}
\includepdf[pages={1-},angle=0,landscape]{DOEquiz.pdf}
\end{document}
