The children can continue learning their Rainbow Words while absent, if you are happy that they have completed their level with confidence and easy recognition then they may move onto the next level. Keep practising all levels as they will be tested on the ones they haven't been when they return to school.
When the children have completed reading a level of words it is also very useful to learn to spell them.
The children are also learning the 'tricky words' they enjoy watching the 'tricky words song' on you tube https://www.youtube.com/watch?v=R087lYrRpgY&safe=true and phase 2 https://www.youtube.com/watch?v=TvMyssfAUx0
There are also lots of episodes of alphablocks to help with your child's blending and segmenting you can find these at https://www.bbc.co.uk/iplayer/episodes/b01cz0p1/alphablocks the cbeebies website also has lots of follow on activities https://www.bbc.co.uk/cbeebies/search?q=alphablocks as does the cbeebies app.