then make them relevant. ... don't say kangaroo jumps 500 metres, say an alien from mars jumps x martian units and ask the student to derive a conversion factor between the martian and earthling units.
or some problems with time dilation.
BUT don't call it "kangaroo jumps 50000 km and we need it cause reality says so"
It can also help you understand what physics you should be using / taking account of.
A metal ball travelling 1m at 3 m/s and I’m pretty confident I can get a good approximation using the basic Newtonian equations.
An irregular shaped object like a Kangaroo travelling 50.000 km at presumably many hundred of meters of per second and I need to think about a lot more! Not least that this kangaroo os travelling about one and a quarter times around the world so the spherical nature of the world needs to be taken into account!
or some problems with time dilation.
BUT don't call it "kangaroo jumps 50000 km and we need it cause reality says so"