We went to Sesame Place in Langhorne, Pennsylvania on a Friday and a Saturday.
Tip #1-Go during the week. The Friday was busy but tolerable. The Saturday was crazy crowded. It was still really crowded after dinner time when it is usually gets less crowded. We went last year during the last weekend in August. It was way less crowded then too. Of course it rained on the Friday.
After last year's rain, we decided to do the water rides the first day if the weather was nice. It was a gorgeous day, so we headed to Big Bird's Rambling River ride.

Tip #2-Do NOT carry money and drivers licenses in your swimsuits. You will lose them. Good news, Sesame Place does have a lifeguard who will swim with goggles to search. Thankfully we did get our licenses back the next day. The money however was long gone.
Tip #3- On busy days there are 2 entrances to Big Bird's rambling River ride. The one over the bridge with the yellow tubes tends to be much shorter than the blue tube entrance.
We alternated between wet and dry rides. Davey still gets really cold in the water so alternating helped him warm up. It seems like most people alternate this way too. So be aware that ride seats are often wet.
We had lunch at the park the second day. Big mistake. The lines were crazy long and the food crazily overpriced. I actually took the kids to ride the carousel while Dave waited in line. The line was really long for the carousel but we still got to ride before Dave made it through the food line.

Tip #4-The park does let you bring in a small cooler. Pack your lunch at least for the kids. The kids meals were $9 each. My kids ate like 4 fries each.
Tip #5- The Count's Splash Castle dumps an amazing amount of water on you (and not just the giant bucket that dumps itself every couple of minutes.) It may be too much for the little ones. My 5 year old loved it. My 3 year old acted like we were trying to electrocute him when taking into here.
Caitlin and Dave are under that water somewhere.
Tip #6-Sky Splash is a huge raft ride. It is the ride with the rubber ducky on top that you can see from anywhere in the park. It is a fast ride. It can be a little scary for the little guys. Both Caitlin and Davey said they never wanted to ride that ride again. Next year might be a different story.
Tip #7-See a parade but get there early. People recommend that you watch the parade where the blue meets the black but really anywhere will work. The characters sing, dance, and high five the kids on the way. Spread your towels out to save yourself some space. You need to get there 20-30 minutes early to get a space. I sat with the kids and Dave got us ice cream to snack on while we waited.

Tip #8-See a show while you are there. We saw Elmo Rocks this year. It was really cute. The kids sang and danced along with the characters. We saw Elmo's World Live last year. Really cute like the TV show. You can pose with Dorothy after the show. We also saw Abby Cadabby's Treasure Hunt last year, which is another good show. Elmo's World Live is the only show that is air conditioned. The rest are outside. Be sure to get there early to get good seats.

Tip #9-Go to a character meal. We had breakfast with Abby Caddabby, Cookie Monster, & Friends this year. It is great because you get take photos with all the characters. The characters also stop by each table to pose again and hang out with the kids. We had breakfast with Elmo & Friends last year. Book early because this meal sells out early. My kids love meeting characters and this lets you do it all at once. We only had to find Elmo and he was luckily at the 1-2-3 Smile With Me when we stopped by. There was almost no line which was a bonus too.

Tip #10-When lines are long, go to some of the attractions that don't have lines or very short ones. The Count's Splash Pad only had lines for the slides.
The Teeny Tiny Tidal Wave pool was great for the kids to just cool off and splash around in.

Davey's favorite place was the Silly Sand Slides. I felt like I could have taken him to a regular park and he would have been as happy but that is another issue.

The kids loved the Mix 'N' Miatch Twiddle Tracks. They are little cars on a train track that the kids can move themselves by pumping a lever. Davey rode this one 3 times in a row since their was no line that day.
The Nets and Climbs were popular but had no lines. My kids loved Cookie Mountain, which was a big tarp mountain to climb. It had short lines.

The kids also loved Monster Maze.

Tip #11-Have fun and make some great memories.