  In this paper, first we give the controlling algebra of Lie triple systems.
In particular, the cohomology of Lie triple systems can be characterized by the
controlling algebra. Then using controlling algebras, we introduce the notions
of homotopy Nambu algebras and homotopy Lie triple systems. We show that
$2$-term homotopy Lie triple systems is equivalent to Lie triple $2$-systems,
and the latter is the categorification of a Lie triple system. Finally we study
skeletal and strict Lie triple $2$-systems. We show that skeletal Lie triple
$2$-systems can be classified the third cohomology group, and strict Lie triple
$2$-systems are equivalent to crossed modules of Lie triple systems.
