Take the kids to Glen Rose to the drive-thru animal preserve one weekend. Takes a few hours to go through, and you can, stop midway at the rec center. Fossil Rim is on the way, but I wasn't overly impressed with that> You might enjoy it though. Go up to Lake Texoma for the day.. Natural beauty at this time of year is a bit challenging but can be done. Go over to Allen to Celebration Park (also has a Splashground there) and picnic there (look on-line for info on it). Go to the Splashground at Village of Fairview (75 and Stacy) and pack a picnic. They have beach volleyball and play area there too.
You can go to Gadzooks by Vista Ridge. There's also Jump Town and Cosmic Jump. If you head South for a daytrip, you can go to Hill Country or Austin. Sign up for Groupon, as it can give some good ideas/sugestions. I've heard that Sandy Lake Park is fun for young kids, a,d you can picnic there. Go to White Rock park for walkimg, hiking, biking, or roller blades. There's also the Chilsom Trail in Plano. Check the park district...City of Plano Parks have a lot of activities and day trips you can do even not living in Plano. Oh, there's a steam train in Grapevine that you can take to Fort Worth.. In Plano, there's a homestead farm. I also have heard the aquarium at Fair Park is good as is the museum there. I'm not a native Texan, so this is not my hometown. Good luck! I hope you find activities that will help you bloom where you are planted. I love it here! (Sorry about the typing, I have my hand in a splint so hard to type).