I find one feature that you will jump higher while you throwing the magnet, and then I use the feature to get the key of level 6.
And this is the pic: 
Is it a design? I very like it. But it looks like a little anti-physics now, if you can think about the momentum in the future I think it will be better.
And from a player attitude, I hope the magnet will be hold in the beginning of the level.