I don't travel with my children at all. I live in the country with no neighbours so kids have to learn to play with each other..... No choice.... I have four free standing pantries with doors on them and that's where I have all my toys. I put child locks on the doors and each day I open a different door .... It's a great form of toy rotation. If you have some bins or something you could pack some of the toys away and switch them up a couple times a week. That way they don't get bored. Also just keep telling them to go play. Or get out a bin if duplo and ask them to build you a castle or tower .... Put them at the table strapped in booster seats with play doh or sensory bins..... How about using masking tape and making a car track around your play room. ... That's a few ideas