Since we all know children benefit from revisiting and articulating what they've recently learned, perhaps the answer is to make plenaries more fun.
Turn plenaries into "Any questions" sessions, with a panel of children commenting on points from the floor. Or set groups to dramatise your subject matter (as a TV report or playlet) or to practise a group presentation of a poem or extract - then the rest of the class can watch and comment in the plenary. Or set up plenary teams, drumming up competitive interest by using quizzes or spelling games for revision.
If the punters enjoy the plenary, everyone will be motivated to ensure it doesn't drop off the end. And anyway, it's not essential to revise immediately after the lesson. The plenary could be a filler later in the day, while waiting for the bell, or even a starter for the next lesson in a series Sue Palmer is a literacy consultant