There would be 10 kids on one team while 9 on another.
Because you can automatically know that 19 is not even then one of the teams will have an uneven amount of kids on their team.
What you would want to do is find the number closest to 19 that is even and not over 19 itself, which would be 18. Now you would divide by 18 and get 9. 9 players would be each team IF it were 18 players but since it’s 19 then one player has to be added with the 2 teams, therefore there would be 10 kids on one team and 9 kids on another.