If you add 1/4 gallon of bleach tonight, and another 1/4 gallon tomorrow, you'll be fine. Pick up a cheapo OTO/phenol red drops testkit while you are buying bleach. Buy a box of borax (http://pool9.net/borax/) too.

You can let the kids in so long as the pH is between 7 and 8 and the chlorine is in the definitely yellow or darker so long as it's not orange. If they want to get in, split your doses (1/8 gallon at a time) to keep it from spiking so high. High chlorine won't hurt them (other than possible red eyes) but it's hard on swimwear.

Once you have stabilizer in the pool the effect of high chlorine will be GREATLY reduced AND you won't lose the chlorine every hour to sunlight.