Activities you could do with your child:
Playing games, especially card games, dice games, dominoes or games involving counting in any form, such as Yahtzee, Monopoly, Ludo, Snakes & Ladders.
In addition, games that support memory, such as memory matching games (www.education.com/worksheets/memory-games) or "I went to the shops and I bought ..." (www.teachingideas.co.uk/memory-time-fillers/i-went-to-the-shops...) can help to develop children's retention skills.
For children in EYFS, Year 1 & Year 2, practice making and recalling pairs of numbers that make a given total, such as all the pairs of numbers that make 10, 8, 5 etc.
For children in Years 2-6, practice times tables: