Working on writing numbers and identify numbers.
Adding and subtracting 0-10 then move to 0-20! This can be done using counters and snacks like m&m's and goldfish to keep them engaged.
Discuss shapes, compare items by biggest and smallest!
Below you will find some online websites that your students can play math games on as well!
https://www.mathplayground.com/grade_1_games.html
https://www.abcya.com/grades/1