This was a complex challenge to solve with a number of parts to it.
Thank you to everyone who submitted a solution, or part solution.
Here are those that showed solutions to many or all of the parts of the challenge.
Firstly, Class 2 from Goodleigh School in the UK sent in this contribution:
First we put all the names into a tally chart by going down the list one by one.
Then we put the tally numbers into frequency order.
It looked like this:
A=$6$ J=$5$ B=$3$ D=$3$ H=$3$ P=$3$ S=$3$ T=$3$ M=$2$ N=$2$ W=$2$
Then we looked at the chart and we saw that there was a T missing,So we knew that Tessa was away.In the block graph the letters were: JMNPS
Next we have Daisy and Rosie from St Nicolas Junior School, Newbury UK who sent in these two pieces of work:
Lastly this came from Eliza at Moonee Ponds Central Primary School in Australia.
We can only include a small part on this page, as she sent in a big file. You can look at the whole file here .