Are you me? Seriously, this has been a family dilemma several times in the last year. Our little guy is 5.
On one occasion we reserved a space in the hatchback floor surface for this, but sounds like you don’t have that kind of space to spare. A tough box should do the trick – depend on the size of the object, could be a shoebox, or a postal cardboard box, or a packing box from something else you’ve bought. Place object inside, and gently surround it with bubble wrap pieces, or t-shirts.
We’ve never resorted to gluing. A few little pieces might fall off in transit, and while a few tears might happen, it might not be too hard to redirect his attention to a fun and challenging repair session.
You’re already packing blankets, towels, and clothes, right? In boxes or bins or something?
So slip the Lego items into the center of the box that holds the sleeping bags or down jackets or throw pillows or whatever. Roll them up in a puffy quilt.
When we moved with Lego items, I just packed them together in boxes as densely as possible, with bits of corrugated cardboard cut and laid in the boxes to divide them up into ‘bearing walls’ and ‘floors’ to keep the things on the top from resting on the things below. I also broke things up into subassemblies where possible. If things can’t slide around and bang into the side walls suddenly, there is less chance of breakage.
[li]If you don’t have the instruction books take a few photos of each kit for reference later in case bits come off.[/li][li]Go over each set and remove anything that will likely come off anyway - on the Falcon probably the ‘radar’ dish, guns, maybe the landing gear. Put in a Ziploc bag.[/li][li]Give the kit a ‘once-over’ making sure the major sub-assemblies are still firmly together[/li][li]Put the entire kit into a large plastic bag to retain any bits that drop off in transit.[/li][li]Pack in a box so that movement is minimised (rolled up bubble-wrap is good).[/li][li]Put Ziploc with removed parts in box.[/li][li]Seal[/li][li]Hope for the best. :D[/li][/ol]
This is what I was going to suggest. Carefully deconstruct each set, and give your son something to look forward to in his new home. For an additional challenge, mix together all the pieces from all the sets.
In getting my own child Lego sets, I have emphasized the use of the toy as a way of learning to use instructions, which is a problem-solving skill in itself. We take sets apart and rebuild them regularly. So, for me I’d just take them apart and put each set in a separate large ziplock bag with its instructions.
I’ve told this to my five-year-old several times, but he just loves to follow instructions. Luckily, after a week or two, he’ll often take an assembled object apart and add the pieces to the general mixed pile. He’ll work on his own creations from that pile about one-quarter of the time.