Printable lacing cards are great for plane trips. Use shoe laces and bright motifs on laminated card, like these Pirate and Princess Lacing Cards from Busy Little Bugs. These don't need a tray so are great for takeoff or landing.
Valentine's Day Lace Card by TheLookingGlassCraft on Etsy
Fine motor skills need practice and learning numbers takes practice, so voila. I made some number lacing cards for my little guy. You can download a PDF of these free 0-10 Lacing Cards from Google Drive here. I printed ours on heavyweight cardstock...