We received several well reasoned solutions to The Money Maze. Lucy and Hayley from Thomas Reade Primary School and Ben from St Michael's C of E Primary School sent particularly clear solutions where they showed each step in turn. Here is Lucy and Hayley's contribution:

The highest integer:
1. $100 (-10)=$
2. $90 (+150)=$
3. $240 (-50)=$
4. $190 (+120)=$
8. $310 (-20)=$
7. $290 (+145(+50$%$))=$
6. $435 (-50)=$
10. $385 (\times2)=$
11. $770 (-10)=$
15. $760 (+30)=$
16. $790$!!!

Lowest integer:
1. $100 (-50)=$
5. $50 (+10)=$
9. $60 (-50)=$
10. $10 (+5(+50$%$))=$
6. $15 (-20)=$
7. $-5 (\times2)=$
11. $-10 (-10)=$
15. $-20 (+30)=$
16. $10$!!!

I like the way you have presented this, girls, it makes it easy to follow the operations.