Here is the site I frequent the most at this point in our homeschooling. I have a 9, 7, and 4-year-old. The computer sits right there where we homeschool, and when we do timed math tests, I pull up “Online Stopwatch” and off we go! Or when the house is a mess, a “countdown to clean” gets everybody pumping, too!
Have a great day! Hope your kids are learning to their full capacity!