diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index ef4c31393d93edb0451aa3fa166173026e36f2f7..6f68bc01d09c58541ec08b7d07ca85041265b38c 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -4,6 +4,7 @@
 - add tuto on how to connect to the Rstudio serveur hosted at the IFB
 
 ## Supplementary exercices
+- Add summary of all code used in the session at the end of the sesssion
 - Write the session_1/bioconductor.Rmd training (and add link in session_1.Rmd)
 - Write the session_1/github.Rmd training (and add link in session_1.Rmd)
 - Write the WDI.Rmd training which will be for a later session