Not that type of magnetic tape, the other!
One of the issues I have had in the past with adhesive magnetic tape is that it comes in rolls. The tape is stored for long periods and the closer you get to the end of the roll, the smaller the radius of the roll and therefore the harder it is to straighten the tape out when affixing small lengths of it to a base.
The solution? When I buy that tape now I lay it up on the outside of the refrigerator door at home. Might not look so attractive on the door but a week or so stored this way and the tape remains flat to the end of the roll.
Still, if needed, you can also slides notes and kids drawings under the tape on the door so you don’t lose any of the domestic advantages of the refrigerator door.