Solution

163653

First name
Penny
School
Hillbrook Primary School
Age
0

Possible answers for 8:
0+8, 1+7, 2+6, or 3+5

4+4 is impossible with the numbers you have because we don't have two 4's.

3 has the least possible number combinations:
0+3 and 1+2
We cannot do subtraction because it said to add up the sum.