I've completed my first short story a few days ago. The story is called 'The Marble.' It's an attempt to write a SF story involving a time traveler. Here it is:
"Jack opened the box as soon as he returned home. His house was once a mill, but after his father was called to sea it was slowly forgotten. The massive wooden wheel broke off and was now lying in the ditch, unseen by overgrown weeds outside."
It sort of starts in the middle and then proceeds to tell the readers how he got the box.
I think it's an interesting start - I like the setting - but it feels a bit like a bait and switch. Your first sentence has Jack opening the box, but rather than continue with that action and its consequences, you retreat into backstory.
The third sentence doesn't work for me. Since I assume the action of the wheel breaking off took place in the past, I feel the need for the past perfect tense, i.e. "the wheel
had broken off." And the final phrase makes it sound like the weeds are unable to see the wheel, when I think what you're trying to say is that the weeds are hiding the wheel.
If the wheel and Jack's mill home are important to the story, maybe you should back up just a smidge and begin your story as Jack returns home, anticipating opening the box once he gets there. Maybe he could pass the ditch and observe the broken wheel as he does so, which would give him a reason to think about his father. As this opening stands, though, I wouldn't read on.