Investigating the Nature and Development of Young Children's Thinking

In particular, our current research focuses on the development of children's artifact concepts. Here are some of the questions we're asking:

  • How do toddlers and preschoolers learn to use tools and other human-made objects?
  • Is the way children approach objects similar to or different from the way adults approach objects?
  • What "mental rules" do children apply when they see someone else using an object?


We are currently looking for children in kindergarten through 8th grade to take a 15-minute online survey. (Younger children will need an adult's help; older children can do it on their own after a parent completes the online consent information). Click here to participate: 

Information for Parents

We're always looking for kids and parents to participate in our projects — and the good news is, it's easy to get involved!

If you have children from birth through early adolescence, email us at or call us at 717-291-3825 with the following information. We'll add you to our database and, if your child is the right age for a current study, we'll talk about scheduling you for a visit.

  • Parent name(s)
  • Child's name
  • Child's date of birth
  • Contact phone
  • Email address

In 2008 we were highlighted in the Lancaster New Era. Click here to read the article, and here's a short video they produced about us.


Frequently Asked Questions

  • What's in it for me?

    First, you know you're advancing the cause of science and knowledge! In addition, children receive a small thank you gift for participating, such as a book or a cute "Child Scientist" t-shirt. You also get to learn a little something along with us; although we don't analyze or report individual children's data (because we're looking for overall trends across entire groups of children), we send families a short report on our findings at the close of the study -- after all of the children have been tested. 

  • How do we get to you? What if I don't have transportation?

    See our directions link at left, or click here. We are located on Old Harrisburg Pike and have free, reserved parent parking right in front of the building. If you are interested in having a child participate but cannot make it to us at F&M, sometimes we can see children at home or day care. Get in touch with us to discuss this option. 

  • Tell me more about your lab space.

    In August 2007 we moved to a beautiful, new research suite. It's a kid-friendly place with a toy-filled waiting room, and if you come with other children, we can arrange for a friendly college student to play with the sibling(s) while the "target" child does the study in another room. We have a diaper changing station, a sink, and a fridge stocked with snacks, all of which come in handy for our littlest participants! The study rooms themselves are equipped with wall-mounted cameras and microphones so that we can record the sessions and review them later. 

  • How long do the projects last?

    Not long! Because we're generally dealing with very little people, most sessions last under 30 minutes, and usually they are single-session events. Occasionally, some studies require two sessions scheduled a few days apart. 

  • What do parents do in your projects?

    Before we schedule a visit with you, we'll give you details about that specific project, and we'll fully answer any questions you have. When you arrive here, you'll sign a consent form, and we'll take some time playing and chatting to be sure your child is comfortable. When we move into an adjacent room for the session itself, you're welcome to sit with your child the entire time -- although of course we ask that you don't do the project for your child. 

  • What do children do in your projects?

    The projects we run are always games as far as children are concerned -- they're designed with little brains and bodies in mind! In other words, everything is made to be fun, short, and interesting. For example, one current study involves preschoolers learning about some unusual new objects, such as a "blicket" that rings a bell and a "dax" that's for crunching up crackers. Subsequently, we watch to see how children use these objects to achieve other goals. The kids usually have fun playing with us; many don't want to leave when they're done! 

  • Do you need children who are a particular age?

    Right now most projects focus on toddlers and preschoolers. However, we maintain a database of local families with kids of all ages, because from time to time projects come up that require the participation of older children and teenagers. This database is kept very securely and no information is shared or sold from it. Please get in touch if you'd like to be added to our database (see above). 

  • My kid is (relatively!) normal. Don't psychologists study kids with problems and disorders?

    It's true that many psychologists are studying important topics in atypical development (for example, studying ADHD or behavior disorders). However, Dr. Casler is a developmental psychologist who primarily studies normal development in order to better understand how typical kids are growing and learning about the world. (This sort of research often has effects in areas such as educational programming, social policy, and theory development.) The research conducted in the Child Development Lab focuses especially on cognitive development. For us, the big question is "How do kids think?"

Still have questions?

Call Dr. Casler at 717-291-3828 or email her at

Who We Are 

Krista Casler, Ph.D. — Lab Director (full bio)

Dr. Casler joined the faculty at Franklin & Marshall College in the summer of 2005. She came from Boston University, where she completed her doctoral degree in psychology under the advisement of Dr. Deb Kelemen. Here at F&M, Dr. Casler teaches developmental psychology, advanced research in developmental psychology, and introductory psychology. As director of the Child Development Lab, the present focus of Dr. Casler's research is on the development of young children’s understanding and use of tools. Outside of the office and lab, you'll usually find Dr. Casler enjoying her family: Jesse, her husband; Josiah, who's 6; and William, who's 3.


Current Projects

Functional Fixedness & Fluency

Most people have a "one tool, one function" bias, meaning that we like to use specific tools for specific jobs. Our lab is exploreing how and when we become fixed on certain functions. In a recent project, we have demonstrated that such functional fixedness appears rapidly after learning the function of an object or tool as opposed to building gradually over time with repeated exposure to objects and their functions. Indeed, it appears that function information immediately limits adults' understanding of tools. 

We are now examining the development of this cognition and related behavior in a study with both adults and children. Participation takes 15-20 minutes and is conducted much like a game. Participants learn about new objects and use them to solve simple problems. 


  • Adults 18 years or older (this group is now full)
  • Preschoolers between 30 and 42 months of age (2.5 - 3.5 yrs old) (this group is now full)
  • Children who are 5-8 years old (this group is now full)
  • Children who are 10-13 years old

Scale Errors with Tools: The Role of Experience

In 2011-2012, we conducted a series of projects exploring a phenomenon known as "scale errors." Sometimes children have a hard time integrating what they see and the actions they choose to take. In particular, children sometimes fail to use information about object sizes, and they may make serious attempts to use objects in impossible ways (e.g., trying to ride on a miniature toy car or legitimately get into a 4-inch doll's bed). We have been exploring why children make these errors and how this impacts their problem solving as they use simple tools to achieve simple goals.

Currently, in summer 2012, we are following up with families that participated over the past year. Parents are being asked to complete a short survey about their child's personalities and habits. We believe that certain individual differences between children may predict their tendencies when making scale errors. 


  • 1- and 2-year-old children (but closed to new families at this time)

Tool Use and Theory of Mind

This is a brief, one-session project and is one part of a much bigger line of research designed to explore how children learn about, create, and problem-solve with simple tools and objects. In this study, we are especially concerned with the social information involved in learning how to use new objects. By observing both typically developing children and those on the upper end of the autism spectrum, we are obtaining valuable information about (a) the role of intentional reasoning in the development of human tool use, and (b) whether the social deficits often observed in autism predict particular patterns of object learning.


  • Children diagnosed with Down’s Syndrome, ages 4 through 8.
  • Typically developing children (no known diagnoses), ages 4 through 6(only a few slots remaining)
  • Children diagnosed with higher functioning autism including those with Asperger's diagnoses, ages 4 through 8 (this group is now full)


The Child Development Lab is in the beautiful Barshinger Life Sciences and Philosophy Building, a facility dedicated to programs in and between psychology, biology, and philosophy. We are conveniently located on Harrisburg Avenue. The entrance to our parking lot (the Williamson lot) is at the street light across from Iron Hill Restaurant and the College Row complex.

We reserve a parking spot right beside the building for our scheduled participants. Look for our red and white sign saying "Child Research Lab Parking."

The lab is suite 144. To find us, enter the main doors of the building, walk straight through the atrium, and then head left down the back hall. We are across from the elevators, on the right.

(For specific driving directions, try plugging 850 Harrisburg Avenue, Lancaster, PA 17603 into your map browser.) 

Contact Information


Dr. Krista Casler
717-291-3828 (office phone)
717-291-4387 (fax) 
Full Bio

Child Lab Location:

Barshinger Life Sciences and Philosophy, (LSP) 144

Telephone: 717.291.3825

Mailing Address:

Department of Psychology
Attn: Dr. Krista Casler
Franklin & Marshall College
P.O. Box 3003
Lancaster, PA 17604-3003

Shipping Address :

Department of Psychology
Attn: Dr. Krista Casler
Franklin & Marshall College
415 Harrisburg Avenue
Lancaster, PA 17603