\author{David J. Benson} \title{Modules for elementary abelian $p$-groups} \begin{abstract} Let $E\cong(\bZ/p)^r$ $(r\ge 2$) be an elementary abelian $p$-group and let $k$ be an algebraically closed field of characteristic $p$. A finite dimensional $kE$-module $M$ is said to have constant Jordan type if the restriction of $M$ to every cyclic shifted subgroup of $kE$ has the same Jordan canonical form. I shall begin by discussing theorems and conjectures which restrict the possible Jordan canonical form. Then I shall indicate methods of producing algebraic vector bundles on projective space from modules of constant Jordan type. I shall describe realisability and non-realisability theorems for such vector bundles, in terms of Chern classes and Frobenius twists. Finally, I shall discuss the closely related question: can a module of small dimension have interesting rank variety? The case $p$ odd behaves throughout these discussions somewhat differently to the case $p=2$. \end{abstract}