Bad news, and I assume your teachers will tell you the same: This still isn't 'lowpoly'. Anything you use a Subdivision modifier on is a subdivision mesh. I'd block it out in a very simplistic way, and then bevel (with a modifier, preferably) any edges that need it. You can use your highpoly mesh as reference, but a…
A re-make of the old Saab car commerical - but in my usual lowpoly style. Made for fun with Maya and Aftereffects, cheers! https://youtu.be/NFc9HiptVLs