Answer by  
                                                                                          Qwitzon (578)
                                                            
                          
                          
                                                          Sanding down to fresh wood is the key, if it has already been outside.  The cells have to be open to receive the stain.  Once stained, you will need several coats (dried between applications) of sealer.  Or, use a desk stain and sealer in one.  Since children will be applying bare skin for hours, think "eco friendly."