Gotta give a thumbs down for the bottom using velcro because it obviously doesn't work if you have to hold it... you should have used a screen door hook or several self closing cabinet hinges
Connect 4 is supposed to be 7 across by 6 high. I've seen cheep knock-offs on a 6x6 grid, but this grid is too small for a meaningful 4 in a row game. I would assume that after a few games, most children would find that all theirs games end in a tie and get loose interest. If you're playing 3 in a row, the first player, if making the optimal moves, can be guaranteed a win no latter than their 5th turn no matter what the second player does. At least in Tic Tac Toe two optimal players will always tie. I would argue that a board of this size reduces the complexity of connect 4 to be less than that of Tic Tac Toe.
OF COURSE THE GROWN UPS NEW. HOPE THEY DIDN'T TELL THE BOY IN THE END LOL LET HIM FIND OUT BY HIMSELF WHEN HE IS OLDER THAT IT WAS 4 INSTEAD OF 3. THEY DIDN'T WANT TO RUIN IT FOR THE BOY. GROWNUPS ARENT IDIOTS U KNOW WHEN IT COMES TO CONNECTING 4.