Jigsaws have benefits including:

• improving spatial skills and shape recognition
• developing memory and patience
• supporting problem solving and reasoning
• providing opportunities for maths talk (counting pieces, 'How many pieces have been put together?' 'How many still left to do?' Estimations etc)
• helping gross motor, fine motor and hand eye coordination 
• relaxing 

The pictures below show how children can make their own jigsaw with a cereal box.