TK vs. Preschool in Concord: How to Choose Transitional Kindergarten or Preschool

If your child turns four this year, you may have a choice between free transitional kindergarten at a Mt. Diablo Unified school and another year of preschool. Both can be great. The right answer depends on your child, your work schedule and what each program actually offers at your neighborhood school.

What Is Transitional Kindergarten (TK)?

Transitional kindergarten is the first year of a two-year kindergarten program in California public schools. It is taught by a credentialed teacher, follows a modified kindergarten curriculum with a strong play and social-emotional focus and is free for every eligible child. California has expanded TK each year; as of 2025–26 it is universal for all four-year-olds, making it a real option for most Concord families.

State TK requirements call for at least one adult for every 10 students (see the CDE TK requirements presentation), and TK is considered part of elementary school, so your child attends a school campus with older students, follows the school calendar and rides the same enrollment process as kindergarten.

Who Is Eligible for TK in 2026–27?

For the 2026–27 school year, children who turn four years old on or before September 1, 2026 are eligible for TK in Mt. Diablo Unified School District. Children who turn five by that date enroll in kindergarten instead.

TK vs. Preschool: Side by Side

The Schedule Gap for Working Parents

This is the factor families most often overlook. TK follows the elementary school day and calendar. At some MDUSD schools TK is part-day, which can mean a pickup in the early afternoon. Even full-day TK ends well before 5 PM and closes for winter break, spring break, teacher work days and the entire summer.

If both parents work, you will likely need one of the following:

• An on-campus before and after school program, where available.
• A licensed child care center that offers school-age care and can accommodate a TK-age child. Ask about eligibility and logistics for your specific school.
• Summer camp or summer care when school is out.

Add up the cost of that wraparound care before assuming TK is free for your household. For some families it still comes out ahead; for others, full-day preschool is simpler and comparable in cost once subsidies are applied.

How to Decide

TK may be the better fit if

• Your child is confident in groups, separates easily and is ready for a bigger campus.
• Your schedule can handle a school-day pickup, or your school has reliable after-care.
• You want your child at the elementary school they will attend for kindergarten.
• Cost is the deciding factor and you do not qualify for child care subsidies.

Another year of preschool may be the better fit if

• Your child is a younger four, still napping or still building social confidence.
• You need consistent 7 AM to 5 PM care year-round, including summers.
• You have a younger sibling in care and want everyone at one center.
• You value a specific approach, such as Reggio-inspired project learning, and small early-childhood settings.

Some families do both: a part-day TK morning with preschool-style care in the afternoon. Ask each program what they can arrange.

How to Enroll in TK at Mt. Diablo Unified

1. Confirm your child's eligibility using the September 1 cutoff.
2. Find your neighborhood school with MDUSD's school locator.
3. Complete MDUSD's enrollment for the school year your child will start. Check the district for the current enrollment window.
4. Gather the documents MDUSD asks for, which typically include proof of your child's age and your address.
5. Ask the school directly whether TK is part-day or full-day and what before and after care exists on campus.

Start with MDUSD's TK and kindergarten page for the current enrollment window and required documents.

Where Super Kidz Club Fits

Super Kidz Club does not offer TK; transitional kindergarten is a public-school program. What we do offer is a Reggio-inspired preschool for ages 2 to 5 that prepares children for TK and kindergarten, full-day year-round hours and a before and after school program for ages 5 to 12. If you are weighing TK against preschool, or trying to piece together care around a TK schedule, come talk it through on a tour. We will give you an honest read on what fits your child.