With the warmer weather (or on rainy days) your dog may not be getting as many walks or even playing in the yard as much. Adding mental stimulation (also called enrichment) to their day can be a big help in curtailing unwanted (and often destructive) behaviors that can be caused by boredom. A few suggestions:
Teaching your dog the "find it" game is an easy one to do. Initially you'll do this while the dog watches from a "wait": toss a few treats on the ground and then say "find it". As the dog gets the point of the game hide a few treats in easy to find spots. Then up the ante and hide the treats in harder to find spots and move the dog out of the room. You can also do this game with a favorite toy.
If you have a "stufficidal" dog that can destroy even the toughest of stuffy toys this works great: Use paper towel or toilet paper cardboard inserts. Put a couple of treats in them and then fold the ends. You can also use small boxes or paper bags for this. Lick mats and Kongs are great. We fill them with kibble or treats and then put peanut butter or plain yogurt (be sure it's not sugar free as the sugar substitutes can be dangerous to dogs) and then freeze or chill them (soft drink kosies are great to hold them upright so they don't make a mess in your fridge). This makes the Kong experience last longer.
Freezing ice cube trays or cookie cutters filled with mixture of plain yogurt, canned pumpkin, broth, canned dog food, even blueberries in water are great treats in the heat and interesting to the dog.
Hide and seek. One person hides and then the other tells the dog to go find. When the dog gets to the person hiding be sure to ask for a sit before rewarding (in this case you are the reward with big praise and attention.) In addition to alleviating the boredom this also helps your dog learn to give wanted behaviors even when excited.