What you have to do is once again use your Flipendo jinx and hit the gnomes with them and they will fall off the rafters once you have done them all then that bit is done.
Then you will have to go out the other side of the barn and you will have to face an alive washing machine when it opens the doors to shoot out bits of washing at you as soon as it opens shoot the flipendo spell at the door and it will bring its life down repeat this 2 more times and its health will go down.
After that you will have to go into the garden where you have to do some degnoming and what you have to do is use your flipendo spell on the gnomes then they will fall on the floor all dizzy then you run up to them press A and you can pick them up then run to the wall and hold down A spin round six times and then through to get a higher score than Fred's.
Throw around at least three times to get the scarecrow target and spin four times to hit the hay stack target. once you have thrown enough of the gnomes then Mrs Weasley will shout you in for bed just press select and you will see your Rememberall and where it says turn in press it.