Hidden Squares

Lots of school groups handed in excellent solutions to this problem.
Well done particularly to Ramu and Atasha from Brookland Primary School for their answers:
 
Square 1 - (1,0) , (1,3) , (4,0) , (4,3)
Square 2 - (1,3) , (0,7) , (5,4) , (4,8)
Square 3 - (20,1) , (16,1) , (16, 5) , (20,5)
Square 4 - (0, 13) , (8,7) , (20,5) , (15,12)
Square 5 - (12,7) , (12,14) , (19,7) , (19,14)
Square 6 - (12,14) , (8,18) , (12,22) , (16,18)
Sqaure 7 - (5,11) , (11,12) , (10,18) , (4,17)
Sqaure 8 - (0,14) , (3,10) , (7,13) , (4,17)
 
The Year 4s from Bradfield Dungworth sent in their picture:
 As


As did the Year 6s from Wingrave C of E:
 
 

For the second part, Harjun sent in this image to show us where the ten squares are:

There is just one square which you've mis-drawn a line in I think, Harjun. Can you see which one it is? Akalya and Michelle from Devonshire Primary School and Esther sent in the coordinates of the 10 squares so we can check that way, too:

1.(2,-3) (-1,-3) (-1,-6) (2,-6)
2.(0,0) (5,-3) (2,-8) (-3,-5)
3.(0,0) (2,2) (0,4) (-2,2)
4.(1,0) (4,1) (5,-2) (2,-3)
5.(2,10) (8,10) (8,4) (2,4)
6.(2,10) (7,8) (5,3) (0,5)
7.(-1,-1) (-1,-3) (-3,-3) (-3,-1)
8.(-4,2) (-9,2) (-9,-3) (-4,-3)
9.(-7,5) (-10,2) (-7,-1) (-4,2)
10.(-7,5) (-5,4) (-4,6) (-6,7)

Thank you to all of you.