\documentclass{beamer}


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\author{NOM DE L'ÉLÈVE}
\title{TITRE DU DIAPORAMA}
\date{}
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\begin{document}

\begin{frame}
\titlepage
\end{frame}

\begin{frame}
\tableofcontents
\end{frame}

\section{PREMIÈRE PARTIE}

\begin{frame}
\frametitle{PREMIÈRE DIAPO}
TEXTE DE LA DIAPO

\includegraphics[width=150pt]{IMAGE.png}
\end{frame}

\begin{frame}
\frametitle{DEUXIÈME DIAPO}
TEXTE DE LA DIAPO

\includegraphics[width=150pt]{IMAGE.png}
\end{frame}

\section{DEUXIÈME PARTIE}

\begin{frame}
\frametitle{TROISIÈME DIAPO}
TEXTE DE LA DIAPO

\includegraphics[width=150pt]{IMAGE.png}
\end{frame}

\section{TROISIÈME PARTIE}

\begin{frame}
\frametitle{TROISIÈME DIAPO}
TEXTE DE LA DIAPO

\includegraphics[width=150pt]{IMAGE.png}
\end{frame}

\end{document}